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Copyright N?._ 


COPYRIGHT DEPOSIT. 
















































Guglielmo Marconi Thomas A. Edison 

( Copyright , Pack Bros ., *V. V ., 1904.) 

Alexander Graham Bell Lord Kelvin 




ELECTRICITY 

FOR 

YOUNG PEOPLE 


BY 

TUDOR JENKS 



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New York 

Frederick A. Stokes Company 

Publishers 
























UBHARY of CONGRESS 
Two Coote' Received 

OCT 15 <30f 

Copynftn Entry 

4X1 

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COPY B. 



Copyright, 1907, by 
Frederick A. Stokes Company 
September , 1907 





Preface 


This is the story of electricity told so that,those 
who are not especially skilled in the science, who are 
not electricians, mathematicians, or experts of any 
kind, can understand how mankind came to find out a 
new power in the world, how they learned its ways, 
how they invented means of controlling it. 

Beginning with the first wonder of the ancients 
over the lightning and the thunder, the magic doings 
of amber, the mysterious power of the lodestones or 
natural magnets, we shall see the steps by which, 
finding out a little here, a little there, wise thinkers 
and patient workers were able to do more and more 
with the new force. We sh-ali see the unaccountable 
ways of an unknown pow^r become at first the 
study of men of the deeper sciences; then practical 
workers will make use of what the men of science 
have learned, until in these early days of the twentieth 
century, the strange genie, electricity, is so far tamed 
as to be our daily friend and helper, tractable when 
rightly guarded. 

Once become man’s servant, electricity is seen to 
be capable of almost any kind of work, and tends to 
replace all other helpers, or to give them better 
methods. 

We shall make some acquaintance with the men to 
whom all this is due, remembering how much their 
work has meant to us, and under what difficulties it 
was done. 


v 


VI 


PEEFACE 


We shall not feel bound to go deeply into all the 
questions and problems and speculations these in¬ 
ventors and discoverers toiled over. Many of them 
merely represent long travels in false paths, when the 
men were following up wrong guesses. But we shall 
try to share the pleasure in the great discoveries, to 
go over again the old paths that were in the right direc¬ 
tion, and by twists and turns led out of the dark 
jungle of ignorance. 

We shall try to learn enough to understand how, 
by the use of electricity, we at our will gain power, 
heat, light, sound ; how we extend our control over 
the earth and the living things upon and beneath its 
surface, how we save time by easier and quicker 
methods of sending intelligence, and overcome space 
by better, swifter, and less cumbrous means of travel 
and transportation. 

In so great a science there is work for unnumbered 
students throughout their lifetimes; and our effort will 
be only to become so acquainted with electricity that 
we may consider it as a daily friend and helper, one 
that must do man’s will, rather than a strange spirit 
of enormous and unknown powers, following a mys¬ 
terious will of its own. 

Illustrations on pages 89, 104, 108, 117, 129, 152, 
163, 166, 171, 207, 215, and 277 are reproduced from 
“The Progress of Invention of the Nineteenth Cen¬ 
tury,” by courtesy of Messrs. Munn and Company. 


Contents 


I. How Men First Knew Electricity . 1 

II. > First Knowledge of Electric At¬ 

traction and Repulsion ... 10 

III. Dr. Gilbert of Colchester . . 21 

IV. The Main Laws Discovered . . 31 

V. Franklin and Contemporaries . . 42 

VI. Galvani, Volta, and the Cell . . 54 

VII. The Pioneers of Science . . .67 

VIII. First Electric Motors, and .Thermo- 

Electricity .76 

IX. The Electric Magnet, the Motor, 

and Induction.86 

X. First Business Uses . 99 

XI. The Telegraph in Early Forms . .113 

XII. Electricity at Work . . . 125 

XIII. Making the Science Practical . . 139 

XIV. The Days of Telegraphy . . . 150 

XV. Cable, Storage Battery and Motor . 162 

XVI. The Electrical Field Widens . . 175 

XVII. Cable, Duplex, and Dynamo . . 187 

XVIII. Cable Recorder, Telephone, and 

Electric Light.201 

XIX. Some Uses of Carbon .... 212 

XX. Electricity Applied in All Fields . 223 

XXI. Electric Waves and Rays . . . 253 

XXII. Electricity in the Twentieth Cen¬ 
tury .282 

XXIII. The Present and the Future . . 300 

Index r .311 

• • 

Vll 





ILLUSTRATIONS 


FULL-PAGE ILLUSTRATIONS 

Guglielmo Marconi—Thomas A. Edison— 

Alexander Graham Bell—Lord Kelvin . . Frontispiece 

FACING PAGE 

Portrait of President Roosevelt Telegraphed by the Korn System 70 

5,000 Horse-Power Dynamos, 25 Revolutions per second, 2,200 

Volt Current, Niagara Falls Power Co.9(* 

The First Telephone.160 

The Telegraphone.200 

The First Electric Engine to Leave the Grand Central Station . 242 

13,000 Horse-Power Turbine for the Electric Development Com¬ 
pany, of Ontario, Ltd.254 

The “Bullock” Generator (3,500 kilowatts) and “ Allis-Chal- 
mers,” 5,000 Horse-Power Engine, World’s Fair, St. 

Louis, U. S. A. ..300 

ILLUSTRATIONS IN TEXT 

PAGE 


The “ Magdeburg Hemispheres ”.31 

Gray’s Discovery ......... 35 

The Leyden Jar and Discharger.39 

Canton’s Electric Chime ..50 

Frictional Electric Machine for Producing Static Electricity . 52 

Galvani’s Experiment With the Frog’s Legs .... 55 

The “ Electrophorus ” 58 

The Gold-Leaf Electroscope.60 

Volta’s Battery or Pile.61 

Voltaic Cells Arranged in Multiple-Connection .... 64 

Voltaic Cells Arranged in Series-Connection .... 64 

Oersted’s Discovery of Magnetic Deflection .... 73 

Ampere’s Solenoid or Coil.78 

Schweigger’s Multiplier ........ 80 

Magnets—Henry’s (A). Sturgeon’s (B).87 

Barlow’s Invention .. . 89 

A Galvanometer ......... 90 

Professor Henry’s Motor ........ 92 


IX 










X 


ILLUSTRATIONS 


Faraday’s Experiment in Magnetic and Voltaic Induction 
Faraday’s Disc-Dynamo, the First Dynamo Ever Built 
The Magnetic Lines of Force 
The Peltier Cross 
Jacobi’s Rotary Motor 
Pixii’s Dynamo (1832) 

Diagram of Two-Part Commutator 
Davenport’s Motor 
Diagram of the Relay Principle . 

The Daniell Battery Cell 
Morse’s First Model—Pendulum Instrument 
Steinheil’s Improved Receiver . 

Cooke and Wheatstone’s Instrument . 

The Grove and Bunsen Cell 
Grove’s Incandescent Lamp, 1846 
Diagram of the Ruhmkorff Induction Coil 
Diagram of the Rheostat 
Diagram of Key and Sounder 
Diagram of Starr’s Lamp 
Hjorth’s Dynamo 
Page’s Electric Motor 
The Siemens Armature 
The Gravity Cell 
The Hughes Printing Telegraph . 

Original Atlantic Cable 
Serrin’s Automatic Regulator (1859) 

Pacinotti’s Machine (1860) 

Plante Storage Battery 
The Reis Telephone . 

Gramme’s Machine 

The Great Eastern Laying the Atlantic Cable (1866) 
Direct Current Dynamos 
Duplex Telegraphy—Stearns-Edison Methoc 
Diagram of Diplex Principle 
Bridge Duplex Telegraphy . 

A Form of Mirror Galvanometer, as Constri 
Thompson 

The Siphon-Recorder and Its Record 
Bell Telephone .... 

Edison’s Chemical Meter . 

The Jablochoff Candle (1877) 


ucte( 


bv Sir William 


94 

96 

97 
101 

104 

105 

106 
108 
113 
115 
117 
121 
122 
128 
129 
134 
140 

143 

144 
152 
154 
160 
161 
163 
166 

169 

170 

171 
176 
180 
188 
191 
193 
196 
198 

202 

204 

207 

208 
210 













ILLUSTRATIONS xi 

The Sawyer-Mann Lamp.212 

Hughes’ Microphone.214 

The Blake Transmitter.215 

Siemens’s First Electric Railway, Berlin, 1879 .... 217 

The Polyphase Induction Motor ( Westinghouse Type) . . 230 

Hertz’s Detector. 235 

Diagram Showing Method of Telegraphing by Induction from 

Moving Train.239 

A Carborundum Furnace ........ 250 

The Crookes Tube, for Producing the Roentgen or X-rays . . 256 

The Fluoroscope . . . . . . . . .261 

A Thirty-Inch Searchlight at Work ...... 268 

Diagram of the Popoff Wireless Telegraph Receiver . . . 276 

Marconi’s Coherer. 277 

Diagram of the Marconi Transmitter and Receiver . . . 280 

The Telautograph.289 

The Cooper-Hewitt Mercury Vapor Lamp.293 








Electricity for Young People 


CHAPTER I 

HOW MEN FIRST KNEW ELECTRICITY 

It is hard for us to think back to the early times. 
If a grown man should try to get rid of all he had 
learned and thought, so that his mind would become 
like that of a very young child, he would be under¬ 
taking a similar task to that which we have to per¬ 
form when we seek to put ourselves in the places of 
the men of old. We cannot feel as they did, or know 
so little; we can only in an imperfect way imagine 
their state of mind, just as in reading a story we 
“ make believe ” and so become ourselves part of it. 

And this faculty of “ making believe ” is not only 
necessary in looking backward. It is also even more 
important in looking forward. Used toward the past, 
it is the faculty that makes history; used toward the 
future, it is the faculty that makes inventions. 

Perhaps you will have more respect for it if we 
give it a dignified name such as men of science have 
adopted, and call this faculty “ constructive imagina¬ 
tion.” By that name the world recognizes this faculty 
as that by which mankind has worked its way out of 
a condition little better than that of the chimpanzees 
or the orang-outans, through the barbarism of 
stone tools and implements, the savagery of the 

1 


2 HOW MEN FIRST KNEW ELECTRICITY 


wandering life and of continual warfare to the days 
of a bettering civilization whose end we cannot see. 

Just as this power of “constructive imagination” 
has brought us civilization, so it has given us, and is 
giving us our sciences. For science is knowledge put 
in order. 

The story of every science must be in many respects 
the same. It is no more than the gathering of facts, the 
putting of knowledge in order for use, and then using 
it. At first, before there is any large body of facts, 
there is no possibility of any science, rightly so called. 
And we shall find it so in the science of electricity. 
It begins only after a certain amount of knowledge, a 
number of facts are known and arranged. 

Probably no one needs to be told that the first of 
the facts in nature that made man acquainted with 
electricity was the thunder-storm. Even the dullest 
savage, the most inattentive barbarian, the least ob¬ 
servant child, could not fail to know there was some¬ 
thing unusual at work in nature’s shop when the white 
thunder-heads mounted upward on the horizon, like 
strange gods peering over the earth’s rim; when the 
heavens darkened, the winds raged, the clouds split 
open, flame shot forth, and the thunder pealed, rolled, 
and died away in long reverberations. These were 
facts no man could help observing—facts that even 
the savage mind must seek to explain by its best 
reasoning — the best use of its faculty of “ making- 
believe,” the constructive imagination. 

And the savage mind did the best it could. The 
savages knew power and force mainly as that of other 
men and beasts they could see, and by these they had 
explained many things. What they did not under- 


HOW MEN FIRST KNEW ELECTRICITY 3 


stand they explained by stories of men and beasts 
they could not see — imagined gods and monsters. 
They knew that their warriors and kings roared and 
struck when angry, and so they explained the thunder 
and the lightning as the expression of the wrath of 
the unseen gods, whose voices stunned their ears, and 
whose angry blows blasted trees or slew beasts and 
men. Such was the beginning of electric “ science,” 
and such for ages upon ages it remained. 

When the electric fire was destructive, it was a 
sign of wrath and fury; when it was harmless flame, 
it was thought to be a sign of the favour or special 
notice of the gods. 

When mankind began to make records in clay, upon 
leaves, and in stone carving, they left us stories of this 
belief. In the early mythologies we find thunder and 
lightning assigned to one god or another. Thunder is 
the Hammer of Thor, the Scandinavian god ; it is the 
Voice of God to the Babylonians and Chaldeans, and 
to the ancient Hebrews, as we see in the Bible most 
poetically in the Book of Job, in the Psalms, and in 
2 Samuel. Thus, in the last, David sings : “ The Lord 
thundered from heaven, and the most High uttered 
his voice. And he sent out arrows and scattered 
them ; lightning, and discomfited them.” This same 
metaphor — where the lightning is spoken of as the 
arrows of the Lord — is in the one hundred and forty- 
fourth Psalm ; and even if it is used poetically, the 
figure shows that in earlier times the lightning was 
believed to be the weapon and the thunder the voice 
of the gods. 

The same belief is in the mythology of the Romans, 
the Greeks and the Etruscans, as, indeed, it would be, 


4 HOW MEN FIEST KNEW ELECTRICITY 


for these peoples also derived their religious and scien¬ 
tific ideas from the peoples of the East. The god 
Jupiter, as lord of the heavens, the upper air, was the 
wielder of the “ thunder-bolts,’* and in statues is shown 
as grasping them in his hands. Zeus, his Greek fore¬ 
runner, also had power over the arrows of the skies, 
and spoke in the voice of the thunder. One story of 
the death of Ajax Oileiis, though not that told by 
Homer, tells how Athena borrows from Zeus the 
thunderbolts that wreck the hero’s vessel. 

That the thunderbolts were thought to be forged by 
the Cyclopses in a volcano only shows that the fiery 
flames of the mountain and its rumbling were thought 
to be like the flashes of the lightning and the rolling 
thunder. That the thunder was thought to signify 
the will of the gods, and that those who were struck 
by lightning and uninjured were thought mercifully 
spared as favourites of the gods, are only natural out¬ 
comes of the general belief. Of more importance are 
the stories that the ancients believed lightning could 
be averted by various devices. The Persians are said 
to have thrust their swords into the earth, during 
thunder-storms — as a sort of protection; probably 
because they had seen swords apparently attract 
lightning. The Greeks put nails into birds’ nests to 
protect the eggs, and the Romans laid bloody axes in 
a row as protection against lightning. These are more 
likely to have been superstitious than scientific devices. 
The Thracians shot arrows against the thunder-clouds, 
which looks like an attempt to scare away bad spirits. 

Once lightning was recognized as a supernatural 
weapon, its symbol in art — a zigzag line — came to 
mean force or power, and the use of it on military 


HOW MEN FIRST KNEW ELECTRICITY 5 


standards, on shields or armour became common. The 
Twelfth Roman Legion under the Emperor Marcus 
Aurelius bore this symbol upon its shields, and either 
from the ornament or from a certain battle in which 
it was unexpectedly victorious, gained the name of 
“ The Thundering Legion.” Being in a deep defile, 
in the year 174 A. D., they were so closely besieged by 
their enemies that they could neither break their way 
out nor get water to drink. Of both troubles they 
were relieved by a furious thunder-storm which re¬ 
freshed them, and threw the besiegers into confusion. 

Some authorities claim that the name of the legion 
had been borne bv it before the date of the battle : 
but, in any event, the battle, the device, and the name 
have come down to us together; and with them 
comes the story that the storm was the result of the 
prayers of Christian soldiers under the Roman stand¬ 
ards. 

Throughout ancient history the thunder rolls, and 
the lightning flashes always in an atmosphere of mys¬ 
tery and superstition —and, as in the legendar}^ disap¬ 
pearance of Romulus in a thunder-storm, is a sign of 
the direct intervention of the gods. And so long as 
anything is accounted for in that way, there can be 
no scientific knowledge of it, since its causes and laws 
will be sought by trying to arrive at the reason for 
the action of the supernatural powers — their wrath or 
their benevolence. Thus men’s attention will be di¬ 
rected to whether good or ill-fortune follows after it 
has thundered on the right or the left, the first being 
thought an omen of the gods’ favour, or to finding 
some reason why this or that great man was killed by 
lightning — as was the father of Pompey the Great,— 


6 HOW MEN FIRST KNEW ELECTRICITY 


or to making others believe they have the power to 
control the lightning, as was done by the women in 
ancient Thessaly, and by various sorcerers. 

That such claims were seriously believed we may 
know from the existence of a solemn argument as late 
as the ninth century, wherein a bishop attempted to 
prove the impossibility that magicians could exercise 
the powers they claimed over thunder-storms. Again, 
it was, even to the times of Shakespeare, a belief that 
witches could raise storms — though to mention this 
is to go too far ahead of our story. 

Undoubtedly some of the claims were merely the 
work of impostors such as the old Greek king of Elis, 
Salmoneus, who, wishing his subjects to regard him as 
a god, drove a chariot over a brazen bridge to imitate 
thunder, and hurled lighted torches about, to seem 
like thunderbolts. Jupiter, either disgusted with the 
poor counterfeit or angered by the impudence of his 
understudy, is said to have slain the sham thunder- 
god with a real stroke of lightning—which might 
have been attracted, we may suppose, by the “ brazen 
bridge,” or the metal armour of this “ little tin god on 
wheels.” 

The poet, Edmund Spenser, in giving the origin of 
the fairy-race speaks of one, 

“ — Elfinor, who was in magic skilled ; 

He built by art, upon the glassy sea 

A bridge of brass, whose sound heaven’s thunder seemed to be.” 

But this was no doubt an independent legend. 

Besides seeing the power of the gods in the violent 
electric disturbance of the thunder-storm, the ancients 
saw in the milder forms of the same agency, signs of 


HOW MEN FIRST KNEW ELECTRICITY 7 


the gods’ good-will or their protective influence. In 
the legend of the Argonauts it is told that they were 
overtaken by a dangerous tempest, when Orpheus 
prayed for deliverance, and soon there appeared two 
harmless flames playing about the heads of Castor and 
Pollux, after which the storm subsided, and the sea 
was still. This old legend made the Great Twin 
Brethren the patron saints of sailors, and probably 
helped in the belief that the same electric light — 
since named the St. Elmo’s Fire — was an omen of 
good to the ship upon which it appeared. 

In the classic authors are frequent references to 
these lights of Castor and Pollux, as well as some to 
a single light, known as “ Helena,” and considered by 
at least one authority (Euripides) as lucky, too, though 
the general belief considered the single light to presage 
storm and wreck, especially if it came after the twin 
lights of the Brethren. The poet Horace, in his Ode 
to Augustus, as translated by Conington, celebrating 
the gods in turn, says of “ Leda’s Twins ” : 


“— Soon as gleam 
Their stars at sea, 

The lashed spray trickles from the steep, 

The wind sinks down, the storm-cloud flies, 

The threatening billow on the deep 
Obedient lies.” 

All these instances serve to show not only the atti¬ 
tude of mind the ancients held toward such forms of 
electricity as are most obvious, but they have some 
scientific value, as proving these appearances to have 
been noted, and, in a crude way, noted as being fol¬ 
lowed by certain results, more or less frequently. 


8 HOW MEN FIRST KNEW ELECTRICITY 


Undoubtedly the ancients must have observed the 
Northern Lights — the Aurora Borealis. But not 
knowing what caused the appearance or wherein the 
brightness that was seen occasionally in the sky dif¬ 
fered from other similar appearances — such as the 
light from shooting stars, and that from lightning 
below the horizon, or the so-called “heat lightning,” 
it is impossible to be sure that any given account is 
really speaking of the aurora and not of some other 
light. 

Besides, owing to superstition — science’s greatest 
enemy—the polar lights when seen were (in Ireland) 
described as a “ rain of blood,” oras“ burning spears ” 
(in London). Then, too, the northern and southern 
latitudes show the lights most frequently, while the 
observers who could have made record of such phe¬ 
nomena were dwellers in the middle latitudes, about 
the Mediterranean or in the northern regions of 
Africa. Altogether it is not strange that the earliest 
definite accounts of the aurora are not much older 
than the sixteenth century — though a few indefinite 
observations date back to the years 502, 688, and to the 
eleventh and twelfth centuries, while Pliny among the 
Romans and Aristotle among the Greeks gave some 
description of these lights in the sky, without attempt¬ 
ing any explanation. 

The action taken by the ancients, even so late as in 
Rome’s days of supremacy, shows plainly that their 
feeling toward these marvels was altogether super¬ 
stitious ; for where lightning struck, it was customary 
to set up altars, erect enclosures, or make sacrifices; 
while any “ fragments of the thunderbolt ” (results of 
the lightning’s action) were “ carefully buried, lest any 


HOW MEN FIRST KNEW ELECTRICITY 


9 


person should be polluted by touching them.” Among 
the Greeks, it was the custom to hiss or whistle to 
avert the lightning’s evil influences, as we learn from 
Aristophanes. 

And, unfortunately, where there is superstition, 
there is a likelihood of “ constructive imagination ” of 
the wrong sort. Believing that the thunder and light¬ 
ning should accompany great events, it is easy to assert 
that they did so. Thus we are told of a flash of light¬ 
ning that struck the Roman capital when Julius Caesar 
was slain, and “ struck away the first letter of the 
name of the prince ” from the inscription on his 
statues — a truly remarkable tale ! 

But history is full of these marvels, and each has 
its interpretation. From the observations of modern 
scientific observers we may gather stories of electrical 
flamings, glowings, and lightning strokes that will par¬ 
allel any of the facts recorded in ancient annals, the 
chief difference being that the ancients were credulous 
and inventive enough to make their stories the most 
striking and poetical. 


CHAPTER II 


FIRST KNOWLEDGE OF ELECTRIC ATTRACTION 

AND REPULSION 

In the times when only the most striking appear¬ 
ances were observed, it might satisfy mankind to see 
in thunder and in lightning, the immediate power of 
their gods. They were simply the amazed and won¬ 
dering observers who trembled and uttered a prayer, 
when threatened by such terrors as are described so 
grandly by the poet and prophet Isaiah : “ And the 
Lord shall cause his glorious voice to be heard, and 
shall shew the lighting down of his arm, with the in¬ 
dignation of his anger, and the flame of a devouring 
fire, the scattering and tempest and hailstones.” 

But though long centuries were to pass before men 
dared to question the thunder-cloud, to gaze stead¬ 
fastly upon the flash of its fire, there were other forms 
of electric action so trivial in their effects as to excite 
curiosity rather than awe, and to incline the mind to 
experiment rather than to reverent prayer. 

There was discovered upon various coasts of the sea 
a certain curious substance. It was light, transparent, 
tough, and inflammable, generally yellow. It looked 
as if it had once been liquid. What it was, the 
ancients did not know. But they followed their 
usual custom of accounting for it by a sort of fairy- 
story. Phaethon had tried to drive the chariot of his 
father the Sun. Coming out of his course, he had 
scorched the earth, dried up oceans, and darkened the 

10 


ELECTKIC ATTRACTION AND REPULSION 11 


faces of the Ethiopians. Jupiter, to save the earth, 
hurled a thunderbolt with such good aim as to strike 
the son of Phoebus from his chariot into the River Po. 

Then the Heliades, sisters of the reckless charioteer, 
through the pity of the gods became poplar trees and 
wept tears that were changed into the strange sub¬ 
stance found on the coasts of various countries, and 
in some places dug out of the earth. Now v HXetczujp 
(Alector) “the shining one,” is a Greek name for the 
sun-god, and “ electron,” the shining thing, was the 
name given to these solid tears — and here is the ro¬ 
mantic origin of the word “ electricity ” — an origin 
that connects it most appropriately with the shining 
brightness of the sun. 

But the tears of the Sun-maidens are known to us 
by another name. We call them “amber,” a word 
that comes to us, most dictionaries say, from the 
Arabic ‘anhar , the ambergris; but I believe the lexi¬ 
cographer Richardson is right in agreeing with some 
German authorities who trace it from their own verb 
brennen , to burn, anbrennen , — the thing that will 
burn. This seems likely, partly because ambergris is 
only “gray amber,” in French, and that would indi¬ 
cate that amber was known before ambergris to those 
who adopted the two words. 

At all events, the substance amber was known and 
prized even earlier than Homer’s days, some twenty- 
eight centuries ago, for a necklace of gold and amber is 
mentioned as being among jewelry brought by a Phoeni¬ 
cian trader to the home of Eumaeus, the old slave of 
Odysseus, for the purpose of keeping the women of 
the household busy while Eumaeus was stolen by his 
Phoenician nurse. Amber is known to have been used 


12 ELECTRIC ATTRACTION AND REPULSION 


even in prehistoric times, and was traded in by the 
Phoenician merchants. It was inlaid in wood, and it 
decorated weapons or shields. But this same name, 
electron, was given by the Greeks to several sub¬ 
stances, and especially to some metallic allo} 7 s; so 
some of the mentions of electron may not refer to 
amber. We learn from Pliny that by the Syrian 
women amber was called “harpaga,” or “ the clutcher,” 
a name we see given also to the harpies. 

Park Benjamin believes this name arose from the 
use of amber spindles in spinning thread. As the 
spindles whirled, rubbing against the women’s gar¬ 
ments, the amber was seen to draw to itself bits of 
thread, the fringe of a garment, or particles from the 
floor. This “clutching” must have seemed a magical 
power to the spinsters, and won for the amber its 
curious name. 

Among the properties for which amber was — and 
still is — valued, is its capacity for taking a high pol¬ 
ish. For a time after being rubbed, as the ancients 
soon discovered, the amber showed a strange property 
— the same property noticed by the Syrian women. 
It drew to itself chaff, straw, bits of string ; these re¬ 
mained clinging for a time. Then, after clinging a 
while, they would be repelled; but the ancients 
seem not to have mentioned this repulsion. Even 
the attraction is rarely referred to in early times. 
The drst written record of this is said to be found in 
the writings of Aristotle concerning Thales of Miletus, 
regarded as the chief of the Seven Wise Men of Greece. 
Thales lived about the time of M^sop and of Nebu¬ 
chadnezzar and it is somewhat doubtful whether he 
was referring to the attraction of amber or of the 


ELECTRIC ATTRACTION AND REPULSION 13 


lodestone, in the tradition recorded by Aristotle. All 
we know of the matter is that Thales is said to have 
believed that the action of the amber or the lodestone 
(natural magnet) indicated the existence of a soul in 
these substances. By this statement the wise old 
philosopher probably meant only that it had “ a power 
of its own” not drawn from outside, for to a philoso¬ 
pher this would be to have a soul. 

It is not to be wondered at that there is some con¬ 
fusion in regard to whether the lodestone or the 
rubbed amber was referred to by Thales, for the 
attractive properties of the two would be classed to¬ 
gether long ages before the real connection between 
the two was even suspected. The lodestone had even 
in the time of Thales, more than six centuries before 
Christ, been known for possibly two thousand years, 
if we may accept the traditions of the Chinese, 
wherein there is an account of an emperor’s con¬ 
structing a chariot for indicating the four cardinal 
points; but this may be merely some old story with 
a modern revision applying it closely to facts known 
later. Humboldt in his “ Cosmos ” tells of Chinese 
caravans being guided by a little revolving figure 
made to point always in the same direction by means 
of a natural magnet. 

It seems doubtful that the magnetic needle was 
known in any but the crudest way even to the Chi¬ 
nese before they acquired the knowledge from some 
of the Western nations, though it is very likely they 
knew something of the natural magnet or ‘‘lode- 
stone ” even before the Greeks. 

And this name “lodestone” is a curious one. The 
first syllable, or first word, “ lode,” meant “ way ” 


14 ELECTRIC ATTRACTION AND REPULSION 


or course, and is connected with our verb lead. The 
term still survives in mining. But lodestone means 
the stone that points the way, and this seems to indi¬ 
cate a very early connection between the magnetic 
ore and the compass-needle. The Greeks gave us the 
word “ magnet,” probably from the place where the 
ore was found, near the town Magnesia, in Lydia; 
but they had an earlier name — the Heraclean Stone, 
either from another town also in Lydia named 
Heracleia, or from the name of Herakles—the Greek 
form of Hercules. But the whole subject is a de¬ 
batable one, and not now worth many words. 

More important it is to tell what they knew about 
“ The Stone,” as Aristotle calls it. That it would at¬ 
tract iron, and hold it, is about the sum of ancient 
knowledge until the time of the poet Lucretius who 
left us a scientific sort of poem on “ The Nature of 
Things.” 

Lucretius, born nearly a hundred years before 
Christ, set forth in a pure, forceful way, and with 
honesty of purpose, the best views of his time, as 
gathered from the Greek philosophers, upon the ques¬ 
tions of man’s relation to nature — that is, upon sci¬ 
entific subjects, and their relation to religious views. 
He gives us in brief a summary of the philosophy of 
the time. He was well read, and likely to give ac¬ 
curate views. 

As to the magnet, he tells us the origin of the name 
from Magneta (magnesia), records its power to “ ducere 
ferrum ,” or attract iron ; and declares that “ men 
wonder at this stone,” since it is able to support a 
chain of hanging rings — an important observation 
since it is the earliest record of the fact that magnetism 


ELECTEIC ATTEACTION AND REPULSION 15 


acts through one piece of iron upon another, pervading 
a series. He also speaks of the iron sometimes seek¬ 
ing the magnet-stone, and then fleeing from it — 
' which, in view of what they knew, seems a difficult 
thing to explain. There seems no likelihood that the 
attraction and repulsion of the poles of magnets were 
known to the Romans at that early day ; and yet 
Lucretius speaks plainly of the jumping about of iron 
filings in a brass vase when the lodestone was put be¬ 
neath the vase, in a way that is explained only by 
assuming he had seen some experiments he had not 
thoroughly understood — experiments such as we shall 
speak of later. 

The whole knowledge of the ancient world was, 
however, no more than a small number of misunder¬ 
stood and unstudied facts, and aimless experiments 
repeated over and over merely from curiosity or for 
amusement. We have seen Thales explaining the 
magnet by saying it had a sonl; and we have omitted 
to mention the Roman poet Claudiaa, who saw in 
iron a food for which the magnet is hungry. Lu¬ 
cretius, though a student and thinker, could say only 
that in the magnet and extending beyond it was a 
sort of vacuum, as the French author Guillemin says 
in his “ Electricity and Magnetism,” adding, “ There 
is nothing, however, in all this worth discussing.” 

In this we agree, since so queer a fact as the attrac¬ 
tion of the lodestone would be likely to find notice in 
every ancient work upon nature or physics, and yet 
the remarks upon it could have value only to the 
student of the past, to the historian rather than to the 
student of electrical science. 

And what is said of the lodestone and magnet is 


16 ELECTRIC ATTRACTION AND REPULSION 


equally true of the mariner’s compass. There are, be¬ 
sides the usual Chinese legends, many stories more or 
less doubtful of its employment down to the twelfth 
century, at which period there is a reference by a 
cardinal in his “ History of Jerusalem” to the use of 
the compass by mariners. Other references tell us of 
the “ rubbed needle ” used by sailors to guide them. 
These early needles were put into straw, mounted on 
cork, or suspended on a point like modern compass 
needles. The best authenticated story tells of the in¬ 
vention of the compass by an Italian, a Neapolitan 
of the fourteenth century. This was about 1320, and 
the man’s name is given as Flavio Gioia. Columbus, 
in his voyage of discovery, noted a fact, already 
vaguely known, that the compass varied from the true 
north ; but he added the important observation that 
this deviation was different in different localities; and 
about five years later Sebastian Cabot noted that the 
deviation was regular for the same needle in the same 
localities — both of these being truly scientific ob¬ 
servations. As to Cabot’s, however, we now know 
that the needle has daily, yearly, and periodic varia¬ 
tions, even in the same locations in certain parts of 
the ocean reached by him, so that his observation was 
far from being an exact statement. 

As the needle was longer known, facts about it 
accumulated, and being written , began to be put into 
form, and to grow into a science. In 1576, Norman, 
a London optician, found out that a needle hung 
freely at its centre of gravity, not only swung around 
an axis until an end pointed northward ; but also that 
the same end dipped so as to be directed downward 
toward the earth. He was angry that he could not 


ELECTRIC ATTRACTION AND REPULSION 17 


easily balance the needles he made, and by the aid of 
“ certain learned and expert men, his friends ” ex¬ 
perimented until he discovered this dipping to be a 
property of the needles. 

Of course while these scientific observations were be¬ 
ing collected, the men of imagination were likewise busy 
in wonder tales of the magical properties and doings of 
the lodestone. Thus there is an old story that Ptolemy 
Philadelphus with his architect had a pretty plan of 
building an arch of lodestones so that it would suspend 
in air an iron statue — a good idea providing it had been 
easy to exactly arrange matters so the statue would 
neither rise nor fall. St. Augustine tells of the same 
device as being carried out by certain “ pagan priests ” 
— not suspecting he is crediting them with what would 
be a miracle of science ; and a legend tells of Mahomet’s 
coffin being so suspended. 

Let any one inclined to believe any of these stories 
buy two magnets, and then, laying a needle on a 
smooth piece of paper between them, so adjust the 
magnets that it would be moved to one except for 
the attraction of the other. Theoretically the experi¬ 
ment should succeed. Practically it won’t. 

Pliny tells the story of Ptolemy Philadelphus, and 
he also records the report that there existed “near the 
Indus ” two mountains, one of which attracts iron and 
the other repels it. It is part of the same veracious 
story that travellers with nails in their shoes cannot 
raise them from the ground when near one mountain, 
nor touch their soles to the other. And in the 
“ Arabian Nights ” the “ Third Royal Medicant ” tells 
of a mountain of lodestone that attracted the iron- 
bolted vessel, extracted the bolts, and thus caused her 


18 ELECTRIC ATTRACTION AND REPULSION 


wreck; but in this mountain there is some magical 
property caused by a strange statue on its top. 

From all this it is easy to see that there was as yet 
nothing worthy of the name of a science of electricity 
and magnetism, though a few bits of accurate knowl¬ 
edge were in print and accessible to students. 

One other sort of electric action was known to the 
ancients in the same imperfect fashion. Besides 
the thunder-storm, the St. Elmo lights, the auroral 
light, the rubbed amber (to which should be added a 
few other substances in which the same property had 
been observed, as “ lyncurium ”— probably tourmaline 
— mentioned by Theophrastus, disciple of Aristotle 
321 B. c.), the lodestone and the compass, a strange 
property was observed in certain animals. 

In the Mediterranean is found a flat fish known as 
the torpedo. The name is an ancient one, given 
because it had been discovered that this fish had the 
power of dealing certain shocks that made men or 
other animals benumbed or torpid. This fish, also called 
“ cramp-fish ’’ and “ electric-ray,” is at times five feet 
in length, and weighs as much as seventy-five pounds. 
This fish was known also to the Romans, being often 
painted on the walls of the buried city Herculaneum. 
Dioscorides, a physician, who lived in the time of 
Antony and Cleopatra, declares that, touched, it cured 
headaches, and in later days it was used to cure gout and 
rheumatism — the oldest use of electricitv in medicine. 

The electric eel of Africa (and warmer parts of 
America), also over five feet in length, is able to give 
a very powerful shock, and there is still a third electric 
animal called the electric silurus, also found in African 
waters. 


ELECTRIC ATTRACTION AND REPULSION 19 

That all these were known to the ancients is 
undoubtedly true; but in a world filled with things 
they did not in the least attempt to explain, there was 
no reason why the peculiar power of these creatures 
should have set men upon especial inquiry. The fact 
that men or horses were violently affected when 
brought into contact with them was known, remarked 
as a mystery, but one no greater than ten thousand 
others. The ancients were like children standing in a 
great laboratory or factory. They saw things happen, 
were amused, or interested, or filled with wonder. 
They told one another about them, may have made 
some vague guesses — and there the matter rested — 
waiting for the birth of a scientific method . For this 
we shall have to come down the ages to the times of 
Queen Elizabeth in England. Now the author of 
“ The England of Shakespeare,” Edwin Goadby, be¬ 
gins his chapter on “ Science and Superstition ” by the 
sentence, “ The English of the Elizabethan age were 
an eminently unscientific people ” ; and he points out 
that the learned men of the time were likelv to be re- 

AS 

garded as magicians and sorcerers, while the pretenders 
to magic were many, and belief in alchemy (the power 
to change one metal into another, as lead into gold), 
in astrology, or the reading of men’s destinies in the 
stars, was nearly universal. 

Bacon was perhaps the most learned and one of the 
most sensible men of his time, and yet he thought little 
of Giordano Bruno’s theory that the earth went round 
the sun, was inclined to think mathematics not a 
“practical” study — as, indeed, it may not have been 
in his time—was sceptical of the value of the telescope 
in astronomy, and drew up a list of things tending to 


20 ELECTEIC ATTRACTION AND REPULSION 


ensure long life that is a mixture of sense and non¬ 
sense. 

Yet it is in this age we shall find the beginnings of 
electric science. For despite the rubbish that still 
clogged men’s brains, books were becoming abundant 
and comparatively cheap; there was some rest from 
religious wars and squabbling, so that men might give 
their time to study and experiment; and though the 
foundations of scientific method can be traced in their 
beginnings to Roger Bacon, and even earlier, and 
were added to by such men as Copernicus, Da Yinci, 
Tycho Brahe, and others, so far as electric science is 
concerned, its beginning is with Dr. William Gilbert. 


CHAPTER III 


DR. GILBERT OF COLCHESTER 

In reading the history of man’s progress in science, 
it often seems that the successful steps were more the 
result of accident than of studious intention. With¬ 
out apparent reason, some man will turn his attention 
to a given subject, and, without evident advantage 
over his fellow men, will advance an art or a science 
by enormous steps. 

So true is this that it often seems to us as if it 
was more a result of men’s attention being devoted to 
a subject than to any real advance in knowledge that 
progress is due. 

But it is probable that this conclusion is a mistake. 
We shall find, on looking more closely into any science, 
that each step usually depends upon the preceding one, 
and until the preceding one be taken, no intellect can 
point out the true path of progress. 

In the history of attempts to navigate the air, we 
find that every improvement in engines making them 
stronger or lighter helps those who try to make 
flying-machines. In our own day, the manufacture of 
auto-cars seems to depend directly upon the ability to 
make light and powerful engines. In the making of 
optical instruments, such as telescopes and microscopes, 
it is the glassmaker who furnishes the material that 
makes more effective lenses possible. 

It may be that the same explanation will apply to 
the enormous advance in knowledge of magnetism that 

21 


22 


DR. GILBERT OF COLCHESTER 


was brought about by the studies of one man during 
the reign of Queen Elizabeth. But, in the absence of 
such an explanation, it certainly is a marvellous hap¬ 
pening that one student, without especial advantages 
over his fellows should by himself have discovered all 
the main principles that underlie magnetic action, so 
that his book, published more than three hundred 
years ago, contains, according to Dr. Whewell, really 
the essence of all the knowledge of magnetism to be 

O O 

found in text-books for long years after his time, and 
until the investigations of such philosophers as Oersted 
and Faraday. It is true that in our own time new 
theories have been propounded, but even if these be re¬ 
garded as entirely established, all honour is due Gilbert 
for the accurate and complete nature of his treatise 
upon magnetism. The story of his labours cannot but 
be an interesting one. 

It is impossible to give the exact date of this man’s 
birth, since there is a disagreement between the 
inscription upon the portrait he gave to Oxford and 
that upon his monument in the chancel of the Church 
of the Holy Trinity of his native place, Colchester. 
The monument declares that he died in 1603, at sixty- 
three years of age, whereas the portrait declares him 
to be in his forty-eighth year in the year 1591 —three 
years younger than he is made by the monumental in¬ 
scription. As Gilbert must have seen the inscription 
upon his portrait, it seems that it is more likely to be 
correct, and we may explain the disagreement by 
supposing a blunder to have been made between 
himself and his brother, who bore the same name, 
William Gilbert, and who afterward edited some of 
his work. 


DR. GILBERT OF COLCHESTER 


23 


Born in 1543, we may say, about fifty miles north¬ 
east of London, in a house which has been preserved 
to our own time, he received a good education in the 
grammar-school of his native town, and at Cambridge 
took his final degree as doctor, in 1569, when Shake¬ 
speare was five years old, and Francis Bacon eight. 

A trip to the Continent brought him the acquaint¬ 
ance of distinguished scholars, and when he began 
practice in England his success was rapid, so that we 
find him president of the College of Physicians in 
1000 when Shakespeare was at the height of his 
career, and physician to the Queen not many years 
later. To Elizabeth’s favour, also, he owed two other 
pieces of good fortune that may have been the special 
helps that brought him fame. In the first place, the 
Queen had him come to court to live, which gave him 
a home rent-free, and she also settled on him a pen¬ 
sion, leaving him to give his time to scientific studies. 

In an article in The Popular Science Monthly , by 
Brother Potamian, professor of physics in Manhattan 
College, New York City, it is pointed out that Gilbert 
owed his success greatly to his insisting upon testing 
the truth of doctrines he had heard, rather than in 
accepting them upon the authority of others. He 
was, as Brother Potamian declares, the natural suc¬ 
cessor of Albertus Magnus and Friar Bacon, both of 
whom made their own experiments, thus asking their 
own questions of nature; and both did work that 
formed a solid foundation for the labours of their 
followers. 

Thus, when it was told to Dr. Gilbert that the 
Italian philosopher, Baptista Porta, asserted that a 
piece of iron “ rubbed with a diamond turns to the 


24 


DK. GILBERT OF COLCHESTER 


north,” he at once put the assertion to the test. Nor 
was he satisfied with only one trial, for he experi¬ 
mented with seventy-five diamonds in the presence of 
many witnesses, using different pieces of iron, and 
bits of wire, floating them on corks, yet without find¬ 
ing that they would point to the north. 

Of course the modern philosopher knows that Porta’s 
declaration referred not to a diamond , but to a lode- 
stone. In the Middle Ages the natural magnet or 
lodestone was called “adamant,” a name applied to 
any very hard substance, and meaning “ unconquer¬ 
able.” The diamond also was called adamant, because 
of its hardness; therefore it was natural for Porta to 
give to the lodestone a name which the Englishman 
could refer only to the diamond. Porta’s statement 
was correct, but was misunderstood. For, indeed, 
Porta himself was a man of science, and imagination, 
a most prolific writer, and founder of a scientific 
academy. He had some notion of the possibility of 
the telegraph, describing how two magnets might be 
made to turn to the same points in concert; but he of 
course had no idea how this was to be brought about 
practically. 

Though these experiments seemed to come to noth¬ 
ing, they show us how carefully Dr. Gilbert tried the 
truth of what he heard asserted. 

And this, as the author of the article already quoted 
points out, was about a score of years before Francis 
Bacon wrote the philosophical books that have led 
some to credit him with introducing the experimental 
method of arriving at scientific truth. 

The account of Gilbert’s years of investigation is 
contained in his treatise on magnetism, the Latin 


DR. GILBERT OF COLCHESTER 


25 


name of which may be translated into “ About the 
Magnet and Magnetic Bodies, and about the great 
Magnet, the Earth.” This book came out in 1600, and 
the third part of the title set forth Gilbert’s greatest 
discovery, namely, that the globe on which we live is 
itself magnetic and may be looked upon as a big 
spherical magnet. When he had found this out, it 
was seen that this fact explained not only the polar 
pointing of the needle, but also its dipping, or point¬ 
ing toward the center of the earth, as well as its 
varying from time to time in one direction or another. 

This great work was the first in its field, and for 
very many years remained. the only treatise of im¬ 
portance upon its subject. It was received by the 
learned men of the time with intense interest. Kep¬ 
ler, the great astronomer, Galileo, and others nearly 
as eminent, made his fame known among scholars 
everywhere. Francis Bacon is accused of jealousy 
toward Gilbert and of a wish to make little of his work, 
in writing that Gilbert “ had attempted a general 
system upon the magnet, endeavouring to build a ship 
out of materials not sufficient to make the rowing- 
pins of a boat.” He also said, with more humour 
than kindness, that Gilbert had so lost himself in his 
subject that “ he had himself become a magnet! ” 

Edward Abbott, a fair-minded biographer of Bacon, 
excuses the philosopher’s faint praise of Gilbert’s 
achievements by the suggestion that “to Francis 
Bacon, impatiently aspiring after vast and general 
conclusions, Gilbert’s researches seemed petty and 
narrow.” 

But we must say, as to this, that Gilbert was prac¬ 
tically following out precisely the method of science 


26 


DR. GILBERT OF COLCHESTER 


Bacon was trying to establish —namely, learning the 
laws of nature by careful experiments, and then seek¬ 
ing ways to make the knowledge of those laws useful 
to men in their daily lives. 

To-day some authorities regard Gilbert, rather than 
Bacon, as the true father of all experimental science; 
and this should be sufficient answer to Francis Bacon’s 
belittlement of the painstaking experimenter. It 
would be kinder toward Bacon to believe that he 
thought Gilbert’s experiments were not exhaustive — 
a belief finding some support from his remark about 
the scantv materials Gilbert accumulated. Others, 
like the Britannica, give the honour of founding ex¬ 
perimental science to Robert Norman, as will be noted 
later. Yet the conclusions Gilbert drew were in the 
main correct, and that is the best praise of his method. 

The second chapter of Gilbert’s book was the first 
treatise on electricity, the first serious study of the 
matter. He advises the reader who wishes to repeat 
his experiments to make a little “ rotating needle of 
any sort of metal particularly light and poised on a 
sharp point.” Rubbing different substances, Gilbert 
brought each near his “ versorium,” or turning-needle, 
to find out whether it was electric. He soon found 
out that many substances when rubbed attract not 
only the needle, but everything else. There is also 
found, however, a number of substances that do not 
attract when rubbed, and he names the two “ electrics ” 
and “ anelectrics,” or non-electrics. 

The word electric is used in its Latin form by Gil¬ 
bert, as an adjective applying to bodies, to influence, 
to attraction, to motion, and so on ; and he was the 
inventor of this use of the word. In all his investiga- 


DR. GILBERT OF COLCHESTER 


27 


tions and reasonings upon them, the learned Eliza¬ 
bethan failed to hit upon certain very obvious facts. 
He did not find out that there were two sorts of 
bodies, one allowing electricity to pass through them, 
the other preventing its passage ; that is, he did not 
find out that there were conductors and insulators. 

The word electricity seems not to have been used 
by Gilbert, its first occurrence being in a work by 
Sir Thomas Browne, the well known physician and 
essayist, author of the “ Religio Medici,” and so on. 
He used it as a noun in his “ Epidemica Pseudodoxia,” 
in the year 1646. Such, at all events is the statement 
of Prof. Silvanus Thompson. 

Gilbert tried some experiments to ascertain whether 
liquids were affected as solids are, and noticed that 
a drop of water is changed in shape when brought 
near to rubbed amber. He also discovered that smoke 
particles were attracted in the same way. It is 
strange that Gilbert overlooked the question of insula¬ 
tion and conduction, or preventing electric action and 
carrying it, for he made elaborate experiments as to 
how electrical bodies would act under all sorts of con¬ 
ditions, testing heated iron, glowing embers, and 
various kinds of flame, through which he learned that 
bodies in flame or very much rarefied were much less 
attracted to his “ electrics.” Lenses enabled him to 
try the effect of the sun’s heat upon his electrics, but 
in this direction he found out nothing interesting. 

But we may well wonder that he discovered so 
much instead of criticising him for missing facts now 
well known. 

As to explaining the results which he observed, 
Gilbert of course had the defects of his time. He be- 


28 


DE. GILBEET OF COLCHESTEE 


lieved that electricity must be something extremely 
fine and delicate, but yet he thought it had substance, 
and declared : “ It is probable that amber gives forth 

something peculiar that attracts the bodies.” If we 
are disposed to criticise this ignorance of the old phi¬ 
losopher, we must remember that we are still guessing 
at the problem which bothered him, and are by no 
means sure that our own explanations are true. 

We read from his notes, not only the story of his 
successes, but of his failures, and see him trying to 
learn the lessons taught by mistakes as well as by ex¬ 
periments that go right. And we need seek no better 
statement of Gilbert’s work than that given by 
Brother Potamian, who says: “ He founded and 

christened the science of electrics. He left it in its 
infancy, it is true, but with sufficient vitality to enable 
it to survive the neglect of years, until at last it was 
taken up and fondly cared for by our Franklins and 
Faradays.” 

Probably Brother Potamian does not mean to over¬ 
look the work of the many great men who preceded 
Franklin and Faraday but uses these names merely to 
signify all modern investigators. 

Upon magnetism, Gilbert’s observations were even 
more valuable than upon electricity. And though he 
thought no substance could be magnetized unless it 
contained iron, a conclusion now known to be incor¬ 
rect, it was not to be expected that he should discover 
that nickel and cobalt were somewhat affected like 
iron, or that under the powerful electro-magnets other 
substances are influenced, as was known later. 

Gilbert either by his own experiments, or by study¬ 
ing the works of others, came to possess all the mag- 


HR. GILBERT OF COLCHESTER 


29 


netic science of the time. He speaks of poles of the 
magnet, naming them from those of the earth, names 
the line joining them the axis, and the line equally be¬ 
tween them, the equator. He finds that magnetizing 
a needle makes it no heavier, as tested by the finest 
goldsmith’s scales. He learns that a magnet cut in 
pieces yields small magnets, like that cut up in having- 
poles and a field of force about each. He tries heat 
upon his magnets, and finds their properties weakened 
or destroyed. He puts substances between magnet 
and iron, and declares the magnetism is cut off (or ab¬ 
sorbed) only by iron. The compass is tested by being 
put into boxes, and found to remain a compass still 
even in an iron box — though this would not have been 
so had his iron box been thick enough to prevent the 
influence of the earth’s magnetism. It is now known 
that the iron (if sufficiently thick) would confine the 
magnetic lines of force, and so prevent a needle acting 
as a free compass needle. 

And this leads us to his greatest discovery — his 
wonderful generalization, “ Magnus magnes ipse est 
globus terrestris ,” meaning “ the earthly globe itself is 
a great magnet.” The fact is admitted to-day. The 
cause is not known with certainty, though various 
theories seem reasonable. 

The value of the discovery was seen in its giving 
at once a reason for and an understanding of the 
action of compass needles, in pointing toward the 
poles, in dipping toward the center of the earth, and 
so on. 

Gilbert added greatly to the facts known in his day, 
found out the laws that govern them, and explained 
the action of the needle by the magnetism of the earth. 


30 


DE. GILBEET OF COLCHESTEE 


Fuller in his “ Worthies of England ” gives Gilbert 
of Colchester a prominent place, and concludes quaintly 
and beautifully, “ Mahomet’s tomb at Mecca is said 
strangely to hangup, attracted by some invisible lode- 
stone ; but the memory of this doctor will never fall 
to the ground, which his incomparable book 4 De 
Magnete’ will support to eternity.” 

Kobert Norman, who in 1570 discovered the mag¬ 
netic dip, was, as heretofore hinted, possibly the true 
pioneer of inductive reasoning quite as much entitled 
to honour as either Bacon or Gilbert; for in speaking 
of scientific authors before his time, Norman declared, 
“ I wish experience to be the leader of writers in those 
arts, and reason their rule in setting it down, that the 
followers be not led by them into errors.” 

Leaving Dr. Gilbert we part with the lonely experi¬ 
menter, for about a year before his death was born 
Otto von Guericke, and von Guericke’s life, 1602 to 
1686, covers a time that introduces us to a number of 
men who contributed to the creation of electrical 
science, notably Sir Bobert Boyle, Sir Isaac Newton 
and Francis Hawksbee. To these three Englishmen 
are due the discoveries, inventions and experiments 
that enabled a host of philosophers to work together 
in studying the laws of action of electricity. 


CHAPTER IV 


THE MAIN LAWS DISCOVERED 

Otto von Guericke was born in Prussian Saxony, 
ancl after being educated as an engineer, and serving 
as such in the army, retired to Magdeburg, his native 
town, and was its burgomaster at the time it was cap¬ 
tured and burned by Tilly, and 30,000 of its inhabit¬ 
ants out of 36,000 massacred. Guericke was then 
only twenty-nine years of age. About twenty years 
later, becoming interested in the study of natural phi¬ 
losophy, Guericke sought to produce a vacuum, and 
invented the air-pump. In 1651 he showed before the 
Emperor at Ratisbon, the “ Magdeburg Hemispheres,” 
two copper half-globes, which, when the air was 



The “Magdeburg Hemispheres.” 


pumped out, could not be separated by fifteen horses 
pulling against an equal number. Yet, air being let 
in, they would fall apart. 

Apparently the news of this experiment came to 
Robert Boyle, then about twenty-four. Son of the 

31 







32 


THE MAIN LAWS DISCOVERED 


Earl of Cork, lie had been educated in England and 
gone abroad till 1644. Then, becoming rich by the 
Earl’s death, he devoted himself to study. In 1654 
he improved the air-pump, and made many experi¬ 
ments. He afterward became one of the earliest 
members of the Royal Society (founded in 1660), and 
discovered certain facts in electricity. Boyle found 
out that amber retains its electricity, that a body 
need not necessarily be smooth to be electrically ex¬ 
cited, and that a cake of resin, and certain other sub¬ 
stances were “ electrics.” He also discovered that if 
the “ electric ” body was left movable, it would be at¬ 
tracted, as well as attract. He reported these experi¬ 
ments to the Royal Society, and made up a theory to 
account for them, and for magnetism, calling the lat¬ 
ter an “ effluvium,” or outflow of the magnet. This 
of course explained nothing, but it helped by giving a 
way of thinking about the magnet’s action. 

Not long afterward, whether knowing of Boyle’s 
discovery about the resinous cake or not, Guericke 
made a ball of sulphur (one of the electrics Gilbert had 
mentioned) and caused it to turn while being rubbed 
by the hands. This was the first electrical machine, 
and came directly from the discoveries of Gilbert. 

With this machine Guericke was able to show a 
stronger action, and thus to perform experiments more 
effectively. And with the greater action came a new 
discovery. When the sulphur was turned and rubbed, 
Guericke noted a feeble glow of light, — which was 
the first dawn of the electric light upon mankind. 

By means of the same machine he found out that 
the electric action or “ virtue,” would act “ through a 
linen thread an ell or more long, and- then attract 


THE MAIN LAWS DISCOVERED 


33 


something.” Here was an experiment that seemed to 
show electricity to be like magnetism, in acting through 
one body upon another. 

Meanwhile two other workers in natural philosophy 
were trying some of the new experiments. Isaac 
Newton, born in 1642, had been allowed to browse 
through the little library of an apothecary, and had, 
though a farmer’s son, and left poor with a widowed 
mother, shown so much talent for mathematics and 
philosophy that he was sent to Cambridge, graduating 
in 1665. Within three or four years, the fall of the 
apple (if we may trust the story for which Voltaire is 
responsible) had set him on the track that led to the 
discovery of the law by which the heavenly bodies 
are governed in their flights through space. Besides 
mathematics, and the laws of optics, Newton experi¬ 
mented with electricitv, and constructed a machine 
like Guericke’s, except that he used a glass globe, find¬ 
ing it better than sulphur. 

It is said that this improvement was probably due 
to Newton, but another claimant for the honour is 
Francis Hawksbee. The date of Hawksbee’s birth is 
not given; but it is known that he made many experi¬ 
ments on light and on electrified bodies, discovering 
among other things that if quicksilver was put into a 
receiver or glass ball from which the air had been al¬ 
most pumped out, upon the air being allowed to force it¬ 
self in again, the receiver would appear filled with light 
that lasted until about half the air had reentered the re¬ 
ceiver. This experiment seems to us the first hint of the 
kind of electric light that is now produced by sending 
electric waves through glass tubes from which the air 
has been almost exhausted. Hawksbee was a mem- 


34 


THE MAIN LAWS DISCOVERED 


ber of the Royal Society in 1705, and Newton had 
been a member since 1672. A son of Hawksbee of the 
same name, became Clerk and “ housekeeper ” of the 
society, and was, like his father, noted for his devotion 
to electric science. Their writings did much to inter¬ 
est learned men in the experiments made by the most 
distinguished scientific men in England, for it was the 
duty of the “ Clerk ” to correspond with scientific men 
of the Continent, acquainting them with the work of 
the Royal Society. Besides this work, the members 
began a museum, which afterward was turned over to 
the British Museum. 

The formation of such a body, and its progress un¬ 
der the patronage of the King, Charles II, shows that 
systematic study of science had begun, replacing the 
single-handed investigations of so-called “ magicians ” 
and secluded philosophers, who began their study of 
the world bv retiring from it. Similar societies had 
been formed in various countries before, but the time 
was hardly ripe for them, as scientific learning was not 
yet sufficiently general. 

The beginning of the eighteenth century saw the rise 
of a new spirit. Frederic Harrison says that in 
“ philosophy, science, in mental versatility, the eight¬ 
eenth century has hardly any equal in the ages.” 
. . . “ It organized into science physics, chem¬ 
istry, . . . electricity.” It was the century in 

which men first worked together knowingly for the 
common benefit— not the age of the lonely thinkers 
in their studies ”; and the science of electricitv was 
taken up seriously and in an orderly way by the able 
thinkers and workers in many lands. 

One of the earliest of these was Stephen Gray, an 


THE MAIN LAWS D1SCOVEBED 


35 


Englishman, who after the researches of Hawksbee was 
the first in twenty years to make electricity a special 
object of study. Sir Isaac Newton had brought other 
subjects more into vogue, by his remarkable discover¬ 
ies. Gray was poor, but was by ingenuity able to 
make use of the commonest things to carry on his ex¬ 
periments, using, as Park Benjamin says, “fishing- 
rods, canes, the kitchen poker, cabbages, and pieces of 
brick,” buying only his glass tubes and pieces of silk. 

Gray discovered that there were conductors of elec¬ 
tricity and also non-conductors. Ilis discovery came 
from his having a glass tube with a cork in each end, 
which on being rubbed attracted light substances. 
The substances were attracted not 
onty to the glass but to the corks, 

— which, not having been rubbed, 
must have gained their electric 
power from the glass. Then he 
tried putting various other sub¬ 
stances in place of the corks, and 
seeing which would become elec¬ 
trified. Gray found that rubbing 
electrified &/Z substances, but that 
the influence escaped from some 
of them, the metallic substances, _ , 

7 7 The bits of paper were at- 

for example, unless they were pre- trac 'e d only when the metai ban 

T 7 J *• was hung to the rubbed rod by a 

vented from parting with it. He conductor - 
hung a metallic ball by threads to a rubbed glass tube, 
and found that if hung by some threads it became 
electrified; but if hung by others it remained unaf¬ 
fected — that is, did not attract the bits of paper by 
which he tested it. 

After making experiments with various threads he 



Gray’s Discovery: 



36 


THE MAIN LAWS DISCOVERED 


found that some permitted electricity to pass to the 
ball, and these became known as conductors. The 
others, preventing it from passing, became known as 
insulators , for insula in Latin means an island, and 
these substances seem to cut off the ball or other sub¬ 
stance from the electricity as water cuts off an island 
from the mainland. 

Gray’s next step was to see how far he could carry 
electricity along his conductors ; and finding a hempen 
string a good conductor , and silk a good insulator , he 
hung a hemp cord by silk supporters and found-he 
could transmit the electricity nearly 900 feet. 

He tried many experiments to find out which sub¬ 
stances would conduct electricity, and made lists of 
conductors and of insulators. The human body was 
found to be a good conductor, and experiments to 
show this became popular, and helped to interest the 
public in the new science ; but the discovery of con¬ 
duction and insulation was an enormous advance, and 
marks the year 1729 as an epoch. For from this time 
electricity could be caused to act at a distance, could 
be brought into a substance, and for a while retained 
there. 

It is interesting to note also that in 1705 Gray 
called attention in one of the Royal Society’s publi¬ 
cations to the likeness between electric discharges and 
thunder-storms — a similarity also noted three years 
later by a Dr. Wall in the case of rubbed amber, with 
its spark and crackling sound. Still another important 
observation of Gray’s is to be told, namely, that a 
solid and a hollow body of the same size, shape, and 
material, act alike when electrified. He reasoned 
from this that the electricity was at the surface, not 


THE MAIN LAWS DISCOYEEED 


37 


throughout the mass, a conclusion now accepted as 
true, and proved by many other experiments than the 
one performed by him. 

The electrifying of the human body seems to have 
been successfully performed first by Dr. Dufay, of the 
French Academy of Sciences, and Gray repeated and 
amplified the experiment, for he was a most eager and 
skillful inquirer into nature. And Gray in turn was 
followed by Desaguliers, a French Huguenot brought 
to England in infancy, who repeated his experiments, 
and who made the observation that bodies that became 
electrified when they were rubbed were not good 
conductors, and vice versa. 

When conductors and non-conductors were thus 
separated into classes, it was discovered, by Dufay, 
first, that all bodies could be more or less electrified, 
provided they were insulated ; second, that water being 
a conductor, it was necessary to see that insulating 
substances were dry, and that conductors often acted 
better when wet; third — and most important—That 
there apparently were two different kinds of electricity, 
or at least that there were two states of electricity. 
One seemed to be caused by the rubbing of glass, the 
other by rubbing resinous substances. He called them, 
therefore, vitreous and resinous. Yitreous electricity 
attracted resinous electricity, and resinous, vitreous — 
each repelling its like. 

Among substances regarded as giving rise to vitreous 
electricity may be named glass, crystal, precious stones, 
animal hair and wool; while resinous electricity was 
believed to be excited by rubbing amber, copal, gum- 
lac, silk, paper, and thread. For a long time what we 
now speak of as positive and negative electrifying were 


38 


THE MAIN LAWS DISCOVERED 


known by the names vitreous and resinous. But now 
we know that the question of whether resinous or 
vitreous electricity results from friction, depends on 
the nature of both substances — so that the same body, 
rubbed by different substances, will produce different 
charges, either vitreous or resinous. 

On the continent, the news of the discoveries of the 
French and English caused activity among the German 
and Dutch philosophers. Boze, a professor in Witten¬ 
berg added to the electric machine, in 1741, what is 
known as the “ prime conductor”; that is, he com¬ 
bined the ideas of Newton or Hawksbee with those of 
Gray, and attached a “ collector ” of electricity to the 
glass frictional electric machine, insulating it, so that 
the electricity might be longer retained. Gordon, in 
1742, used a long glass cylinder, instead of Newton’s 
globe, and caused it to be rubbed by a fixed cushion, 
instead of by the hand. In this way, the machine 
became really effective, was rapidly improved in its 
mechanical construction, and operators could draw 
from it long sparks, of force and intensity enough to 
set fire to alcohol and even to less inflammable sub¬ 
stances. With the ability to bring about strong 
electric action, many new and striking experiments 
could be tried, and more knowledge obtained of the 
laws of electric action and its conditions. 

But a greater step was soon to follow. The prime 
conductor served to receive the electricity from the 
rubbed cylinder, but did not afford means for storing 
it up, since the insulation was imperfect. Conse¬ 
quently, men sought a way of collecting electricity 
inside of some insulating vessel. The simplest idea 
was to put it inside of a glass bottle. As early as 


THE MAIN LAWS DISCOVERED 


39 


1745, a Bishop of Pomerania,, named Yon Kleist, put 
mercury into a bottle, and led a wire down into it. 
Then by means of a rude form of electrical machine 
he conducted the electricity along the wire and into 
the water. The experiment succeeded, and in remov¬ 
ing the bottle he received a shock that seemed to him 
very strong. 

During the next year, the same experiment was also 
made with water in the bottle, probably independently, 
by a Professor Muschenbroeck of Leyden, or by a 
pupil of his named Cuneus. Muschenbroeck says of 
the shock received, “ I felt myself struck in my arms, 
shoulder, and breast. I lost my breath, and it was two 
days before I recovered from the effects of the blow 
and the terror.” 

The unexampled force of this new form of electric 
action caused great interest 
and excitement in all parts 
of Europe. The bottle, 
known as the Leyden jar, 
was ea^erlv studied bv a 
number of philosophers, de¬ 
spite Muschenbroeck’s 
alarming declaration, “ I 
would not take a second 
shock for the kingdom of 
France.” For the first 
time it was made possible 

to collect and hold electric- The Leyden Jar and 

Discharger. 

ity in a receptacle that could 

be carried from place to place, and to release the 
condensed charge by touching a conductor to the 
receptacle. 















40 


THE MAIX LAWS DISCOVERED 


Houston, in his exhaustive work on “ Electricity in 
Everyday Life,” truly a small encyclopedia of the 
whole subject, has by quotation from an old treatise 
given a good idea of the interest excited by the in¬ 
vention of the Leyden jar. “ Then, and not till then,” 
says the old author, Cavallo, “ the study of electricity 
became general, surprised every beholder, and invited 
to the houses of electricians a greater number of spec¬ 
tators than were before assembled together to observe 
any philosophical experiments whatsoever.” 

The Abbe Nollet, a French experimenter and a 
friend of Dufay, exhibited the power of the Leyden 
jar by causing three hundred soldiers to hold hands 
forming a chain, and then in the presence of Louis XV 
sending the electricity through them all. Other 
Frenchmen sent the current through a circuit about 
two miles and a half in length ; and once the basin of 
the fountain at the Tuileries, containing an acre of 
water surface, formed part of the circuit. The Eng¬ 
lish Royal Society outdid even this feat under the 
direction of Sir William Watson, noting so far as 
possible the laws of the action of the jar, and ascer¬ 
taining that the electricity was felt instantaneously 
through 12,276 feet, over two miles of wire. 

It was learned by these experiments that to get 
good effects there must be a conducting substance on 
the outside as well as on the inside of the jar; and 
Watson used tin foil on both outer and inner surfaces, 
finding it more convenient and effective than water. 
The electricity received from the machine was ijosi- 
tive (or vitreous to use the old name); and just as when 
we magnetize a bar one end tends northward and the 
other southward, and two north poles repel each other, 


THE MAIN LAWS DISCOVERED 


41 


but north and south are attracted, so in the Leyden 
jar it was found that to charge either surface posi¬ 
tively, made the other surface negatively charged. 

At first jars were made of larger size to get stronger 
effects, and then it was found that a number of small 
jars could be connected together by conductors — 
inner surface being connected to inner, and outer to 
outer throughout the series — and thus the effects 
of a single large jar could be brought about by a 
“ battery ” of smaller jars. 

The means of condensing electricity into receptacles 
being found, there followed within very few years a 
large number of discoveries as to its properties. But 
in order that we may follow the progress of the 
science it is necessary that we should get a better 
idea of the nature of the subject these men were 
studying, some idea of its properties and laws. 


CHAPTER Y 


FRANKLIN AND CONTEMPORARIES 

We know all things by means of our senses. The 
effects on sight, hearing, feeling, taste, and smell are 
the only means by which we know of the outer world. 
About these effects and their causes we can reason in 
our minds, making guesses at how things will act, and 
why they act as they do. We can correct the report 
of one sense by another — as when we see that a per¬ 
son is in one place though some echo, perhaps, makes 
the ear report his voice as coming from another place. 
We can make guesses about causes, and then test our 
guesses by experiments, and in this way separate true 
causes from apparent ones. We can compare things 
unknown with things known, see likenesses and differ¬ 
ences, and thus form an idea of what is likely to be 
true even of the unknown. 

As to electricity, we can know only its effects upon 
the senses, or its effects in changing other effects on 
the senses. Thus it is that motion, heat, light, sound, 
weight, odour, taste are found by us in substances; and 
for ages these were all men knew of matter. Then 
began the collecting of facts due to something that 
seemed to cause some of these effects. A bit of rubbed 
amber caused motion. Light straws were seen to 
change place. Again the rubbing of similar sub¬ 
stances in a more effective way showed the production 
of heat, and light, and sound, all produced by the con¬ 
dition caused by the friction of certain substances. 

42 


FKANKLIN AND CONTEMPOBAEIES 43 


A name was given to this condition. The substance 
was called electrified , and that by which it caused 
effects was called electricity. Then it was said that 
electricity drew things to one another; repelled 
things from one another; warmed them, even burned 
them ; would act better through some substances, and 
not so well through others; could be held in the con¬ 
denser or Leyden jar, and then be let free at will. 
Next it was found that there were either two kinds or 
two states of electricity, and that these sought each 
its opposite, and .when combined seemed quiescent, 
when separated by non-conductors were as if confined 
and seeking release and reunion, which came about 
by action from the positive to the negative — from 
the vitreous to the resinous. 

All these laws being known, more or less certainly, 
men began to guess about what electricity could be. 

Thales named it a “ soul” or spirit, which was little 
more than an empty word. Boyle spoke of an 
“ effluvium,” or outflow, which suggested a way of 
action. Dufay, and an Englishman named Symmer, 
called electricity “ fluid,” and believed all substances 
to contain two kinds, weightless, that united had no ac¬ 
tion, but separated by rubbing,gave rise to the observed 
action. And this was the state of men’s guessing to 
about the middle of the eighteenth century, though 
Sir William Watson had added the suggestion that 
rather than two fluids, electricity might be one fluid 
in two states — the positive and negative. 

Such, put in brief general form, was the state of 
electric science when Benjamin Franklin began his 
experiments and researches and his attempts to form a 
clearer idea of electric action. Franklin was always 


44 FRANKLIN AND CONTEMPORARIES 


interested in all subjects of learning, and besides being 
printer, author, and owner of a newspaper, had been 
member of the assembly and postmaster of Philadel¬ 
phia. He organized the city’s first police and its first 
fire-company, a militia, a hospital; he gave his atten¬ 
tion to the paving of the streets, founded the Uni¬ 
versity of Pennsylvania, the American Philosophical 
Society and the great Library Company of Phila¬ 
delphia. 

He became interested in electricity, and when the 
question whether thunder and lightning were caused 
by electricity in the sky occurred to his mind, his 
ingenious mind taught him a way to find out the truth. 
He had already drawn up a paper showing that the 
effects of electricity were the same as those caused by 
lightning. 

It was in 1749 that Franklin noted the likenesses 
between lightning and electricity. He found they 
agreed in giving light and in its colour, in zigzag 
motion and swiftness, in being attracted by metals 
and conducted by them ; in passing through water or 
ice, rending bodies they pass through, killing animals, 
melting metals, firing inflammable substances, and 
having a sulphur smell. These resemblances, added 
to the noise made by an electric discharge, caused 
Franklin to believe the two might be proved to be the 
same. 

He hoped that a spire would be built in Philadelphia 
so that he might in some way attract the electricity 
from thunder-clouds. But, since no spire was built he 
became impatient, and decided to use a kite for the 
purpose of carrying a string into the stormy sky. 

It had already been found that pointed conductors 


FEANKLTN AND CONTEMPORARIES 45 

*• 

best attracted electricity, and received it with the least 
disturbance. It is said that a friend of Franklin’s, 
Thomas Hopkinson, discovered the power of points to 
receive or to set free electricity ; and this is referred 
to in a letter of Franklin’s dated July 11, 1747, and 
experiments proving it are described. So he placed a 
pointed wire about a foot long at the top of a kite 
made of a large silk handkerchief stretched on cedar 
sticks. To the kite was attached ordinary twine, but 
after the kite was raised, a piece of silk ribbon was 
led from the twine, and a key tied to the same place. 

Of course the idea of Franklin was that if electricity 
was in the clouds, some of it would be attracted by 
the steel wire, would act along the conducting twine 
and key, and would be insulated by the silk — a non¬ 
conductor so long as it was dry. With his son Frank¬ 
lin stood under a shed to keep the silk ribbon dry, and 
awaited results. This was in June, 1752. 

After some waiting the fibers of the twine were 
seen to stand apart — repelling each other, because 
electrified the same way. Then approaching a 
knuckle to the key, he received an electric spark such 
as came from electrified bodies. A Leyden jar was 
brought, and on being applied to the key collected 
electricity with which the usual experiments could be 
performed. 

For the first time the lightning of the thunder-cloud, 
and the electricity known on earth were proved to be 
of the same essence. Franklin — the printer-boy — 
• had dared to steal a part of Jupiter’s thunderbolt, in 
order to prove that even the lightning obeyed laws 
that the brain of man might understand, and had 
bounds beyond which it could not stray. 


46 


FRANKLIN AND CONTEMPORARIES 


It is not to be wondered that in his old age the 
American philosopher was glorified by the praise — 
Eripuit ado fulmen , sceptrumque tyrannis. “ He 
snatched the thunderbolt from the skies, the scepter 
from tyrants” — a line written by the French states¬ 
man, Turgot, and imitated from the Latin author 
Manilius. It was praise well-earned by the superb 
courage that delied the lightning in the hope of gain¬ 
ing knowledge for the good of mankind. 

As it was already known that the lightning was 
ended when it had reached earth, Franklin’s inven¬ 
tive mind at once saw the possibility of placing a 
conductor upon houses, that would give the lightning 
a safer path to earth, and thus he invented the light¬ 
ning-rod— a pointed conductor ending in the earth. 
And this was not only a path for the lightning stroke, 
but also a means of withdrawing smaller charges of 
electricity, that lightning might less often break forth. 

After Franklin’s researches had made experi¬ 
menters familiar with the power of points to charge 
or discharge bodies, with which they are connected, 
they were often put to this use in apparatus — es¬ 
pecially on the receivers of frictional electric machines. 

From the Leyden jar, now that its charge was 
identified with the electricity of the clouds, there was 
much to be learned, of both lightning and electricity. 
Franklin studied the subject fully, declaring that the 
rubbing of glass did not create but collected the 
“electric lire,” and then gave it out to any body pos¬ 
sessing less. The inner coating of the Leyden jar 
received an unusual amount of the electricit}', while 
the outer coating lost a similar amount. This was his 
idea of one being charged positively, or in excess, 


FRANKLIN AND CONTEMPORARIES 


47 


having a the other having a minus or negative 

charge. 

Whatever his use of terras, he at least saw the truth 
that the two coatings were in a different state elec¬ 
trically, and that when a conductor was made to join 
them there was violent passing of electricity between 
the positive and the negative, and then they were in a 
like state, neither giving forth electricity. Therefore 
he was inclined to what was known as the “ single¬ 
fluid ” theory of electricity which ascribed electric 
action to the difference of the amount of so-called elec¬ 
tric fluid in two bodies. Rubbing two bodies together 
causes electricity, it was believed, to pass from one to 
the other, whereby one becomes overcharged, the other 
undercharged, or one positive, the other negative. 

Franklin also thought that the “ electric fluid ” re¬ 
pelled itself, so that two positively electrified bodies 
showed repulsion. Why two bodies negatively 
charged should show repulsion is, on his theory, not 
so easily understood. But though these early theories 
were great helps in finding the truth or the truer 
theories of later times, they are now replaced, and we 
need not therefore bear them in mind except as help¬ 
ing us to know the meanings of terms that came into 
use while those theories were held. 

Nor must we think the old theories indicated igno¬ 
rance in the authors of them. They were often the 
result of much deep thinking and experiment, and are 
usually nearer right than wrong. Though to-day we 
do not think of electricity as a “fluid,” yet we still 
find the easiest way to explain many kinds of electric 
action is likening it to the flowing of water in pipes 
and from reservoirs. 


48 


FEANKLIN AND CONTEMPOEAEIES 


While Franklin’s kite experiment is perhaps the best 
known, there were at a little later time in Europe a 
number of electricians trying similar experiments by 
using long iron rods to attract the lightning. Among 
them may be named D’Alibard, who owed the sugges¬ 
tion to Franklin, but who drew sparks from the clouds 
some weeks before the flying of the Franklin kite. 

But there were many sceptics who chose to doubt 
the experiment, as related by the American, so long 
as this was set forth only upon his authority. The 
Eoyal Society of London was one of the doubters, but 
soon admitted the importance of the occurrence. 
Franklin’s account was translated into foreign lan¬ 
guages, and in various ways and various cities phi¬ 
losophers sought to draw lightning from the skies. 
Among these disciples of the American were the great 
Buffon, the French naturalist; Beccaria, the Italian; 
Bomas, another Frenchman, and a Eussian, Professor 
Bichmann. Bomas used a kite, but added a wire to the 
cord, and succeeded in attracting a strong charge ; 
while Bichmann, having a metal conductor arranged 
from the roof of his laboratory and ending in a rod 
through the ceiling was instantly killed by a flash of 
lightning that struck the iron rod, entered his body at 
the forehead, and apparently left through the left 
foot, bursting the shoe. 

Considering the daring of experimenters and their 
ignorance it is remarkable that the death of Professor 
Bichmann is the only tragedy recorded in these early 
days of the science. Many others had set up pointed 
rods, and had discovered that there was often elec¬ 
tricity in the atmosphere even when no thunder-clouds 
could be seen, or when the sky w T as cloudless. This 


FRANKLIN AND CONTEMPORARIES 


49 


electricity is usually positive, especially in clear 
weather; in rainy weather it is generally negative, 
but may change often and suddenly. 

Among noted students of electricity at this time was 
John Canton, an Englishman born in 1718, and thus 
about thirty-four years of age at the time of Frank¬ 
lin’s kite-flying. He had already been interested in 
the Leyden jar, and had made many experiments in 
electricity and magnetism, being elected to the Royal 
Society and awarded a gold medal for a paper on mak¬ 
ing artificial magnets. He repeated Franklin’s proof of 
the identity of lightning and electricity, being the first 
in England to do so, and read a paper describing his 
observations in which he mentioned the discovery 
that some clouds were negative and some positive. 
He was in correspondence with Franklin and became 
his friend. 

He remained as he had begun, a schoolmaster, but 
to him we owe a number of discoveries in electric 
science. He found out that resinous or vitreous elec¬ 
tricity might be excited in the same substance when 
rubbed by differing substances, and that the smooth¬ 
ness or roughness of the surface at times determined 
the kind of electricity produced. A glass tube, half 
rough and half smooth, was made bv the use of a 
single rubber to produce both kinds of electricity at 
once. He invented putting an amalgam of quicksilver 
on the rubber of the electrical machine, thus increasing 
its action. But, a most important step forward, he 
discovered that electricity could be developed in a 
substance by the mere approach, without contact of 
an electrified body. This was the first discovery of 
electric induction , and was made in 1753. 


50 


FRANKLIN AND CONTEMPORARIES 


This helped to explain the attraction and repulsion 
of light bodies by electrified substances. Suppose a 
cork-ball hung by a thread to be brought near a posi¬ 
tively electrified rod of metal. At once, by this in¬ 
duction, the cork is electrified negatively on the side 
nearest the rod. It is then drawn to the rod, touches, 
is electrified positively by the stronger charge, and is 
then repelled since positive repels positive. It re¬ 
mains repelled until discharged by being touched. 
Then it is again attracted as before. 

Canton in this way made what is known as the 
electric chime , placing little bells so they would when 


Canton’s Electric Chime. 

positively electrified attract light balls that rung 
them, were then repelled, struck another bell that dis¬ 
charged their electricity, were again attracted, and so 

















FRANKLIN AND CONTEMPORARIES 


51 


on in a cliime. He used this chime in an apparatus 
for collecting electricity from the air, and it began 
to ring when the apparatus was electrified by the air. 
By means of his experiments Canton learned that the 
air in a room could be electrified either positively or 
negatively, and so remain for some time. 

Beccaria, the Italian, made at this time a number of 
observations showing that water conducts electricity 
imperfectly except in large quantities, and that air 
near a body that had been electrified gradually ac¬ 
quired the same electricity, and parted with it but 
slowly, thus supporting Canton’s induction discovery. 

Robert Symmer, having noticed sparks and crack¬ 
ling when he pulled off his stockings, began to experi¬ 
ment with them, and concluded that the colour and 
material of the stockings made much difference in the 
electrical action. He charged a Leyden jar from the 
electrified stockings, and was led to adopt the two-fluid 
theory of electricity by his experiments, believing that 
the actions noted were explained by supposing two 
fluids that existed together, and gave rise to electric 
disturbance when their equality or equilibrium was 
disturbed. 

So many men were now at work making experi¬ 
ments that space cannot be given to them all, especially 
as later observers have found out simpler or more di¬ 
rect methods of proving the facts they brought out. 
Thus it was found that a number of minerals became 
electrified when heated; that some substances showed 
electrical changes when melted, and that the shock 
given by the torpedo fish was an electric shock, pro¬ 
duced by a true electrical apparatus. 

In 1760 there was a most important change made in 


52 


FRANKLIN AND CONTEMPORARIES 


the frictional electric machine. Ramsden used a glass 
disk instead of the cylinder, — to the machine’s mani¬ 
fest improvement. But more important than any 



Frictional Electric Machine for Producing Static 

Electricity. 


general observations, or even the improvements in ma¬ 
chines were the accurate researches carried on by the 
deep scholar Henry Cavendish, who in 1771 published 
in the papers of the Royal Society of England, a 
theory of electricity. Cavendish measured the resist¬ 
ance of various substances to the passage of electricity, 
examined the capacity of glass plates to hold elec¬ 
tricity, and studied the results of passing the electric 
spark through mixtures of gases. Others had taken 
apart water into oxygen and hydrogen by passing elec¬ 
tricity through it; and Cavendish by experiment was 
able to make them again into water by exploding an 
electric-spark in the right mixture. But though these 



















FRANKLIN AND CONTEMPORARIES 


53 


were the beginnings of electro-chemistry, a science 
possibly destined to produce the greatest effects on 
human life in the future, the investigators did not carry 
them further, and it remained for future years to de¬ 
velop the hints they contained, just as coming men 
will develop ours. 


CHAPTER VI 


GALVANI, VOLTA, AND THE CELL 

As electricity was more and more studied, inven¬ 
tors tried to devise ways by which it could be meas¬ 
ured. Cavendish had examined into the resistance of 
conductors, and Coulomb, who lived about the same 
time, took up the question of quantity. He devised a 
way to measure the force of electric or magnetic ac¬ 
tion. For this purpose he made a glass jar in which 
from a line wire hung a needle of shellac having a gilt 
ball at its end. By lowering a charged rod into the 
jar, the ball was repelled, and the wire twisted to an 
amount measured on a scale, thus showing the 
strength of the repulsion from the rod. A similar 
balance was used to test magnetic force. 

From the experiments made Coulomb declared that 
the action of magnets was inversely proportional to 
the square of the distance ; that is, at half a given dis¬ 
tance the force was four times increased ; at one-fourth 
the distance, sixteen times increased. This same law 
applies in the case of electricity, when the balls elec¬ 
trified are small. His balance also showed that elec¬ 
tric charges repelled or attracted with a force equal to 
th q product of the charges for a given distance. 

Coulomb gave out a double-fluid theory of magnetism 
in 1780, which was little more than an adapting of the 
electric theory to the actions of the magnet. We 
need not discuss it, since the fact that one magnet will 
magnetize many others without losing power seems a 

54 


GALVANI, VOLTA, AND THE CELL 


55 


fair proof that magnetism is not to be considered a 
fluid; besides, modern theories seem more probable. 
But Coulomb’s measurements enabled him to find out 
just how magnetism was distributed in magnets, and 
that electricity distributed itself equally between 
spheres of the same size, but differed in density at 
various points, and on bodies of various shapes, and so 
on. In short, he Collected a great number of careful 
observations and attempted to explain them by a 
theory that helped greatly in the exactness of the 
science, and practically showed how to make con¬ 
ductors, condensers, and insulators more effective and 
perfect — all of which was most valuable to later ex- 



Galvani’s Experiment With the Frog’s Legs. 

perimenters, and secured for Coulomb the fame of 
having the electrical unit of quantity (that unit by 
which amounts of electricity are measured) called in 
recent years by his name — the coulomb. 

The last few years of the eighteenth century saw 
also the rise of what was almost a new science of elec¬ 
tricity, through the discoveries of the Italian Galvani, 
a professor in the University of Bologna. One even- 



56 GALVANI, VOLTA, AND THE CELL 

ing in liis laboratory while investigating the effect of 
electricity on animal organisms, he used frogs’ legs as 
a means of detecting delicate electric charges. Then 
having bound them together with copper wire they 
were hung against an iron railing in a window, and 
immediately became “ powerfully convulsed.” Such 
is one story of the happening. Another is quite differ¬ 
ent, and says that frogs’ legs broth had been ordered 
for Madame Galvani because of her having a cold. 
The skinned legs were lying on a table near an elec¬ 
tric machine in action. An assistant touched them 
with a metal instrument, and they were violently 
affected. Madame Galvani noticed the occurrence, 
and her husband investigated it. The first storv is 
favoured by Dr. E. J. Houston for the reason that a 
document exists showing Galvani had used frogs to 
test for electricity several years before the date given 
to that story, whereas the frogs’ legs-broth incident is 
dated later than the first. Probably the discovery was 
earlier than 1786. 

Though a Dutch physician, Swammerdam, had more 
than a hundred years earliershown that frogs’legs would 
twitch when touched by metal wires, Galvani undoubt¬ 
edly knew nothing of this when he announced his dis¬ 
covery of “ animal electricity.” He thought electricity 
might be secreted by the brains, and then stored in the 
muscles, as if in Leyden jars, from which the nerves 
conducted it. So he formed a branched fork of metal 
wires, copper and silver, and caused convulsions of the 
muscles by touching one end to them, and the other 
to a nerve. These experiments were repeated in 
various ways and an account of them published. 

Galvani himself lost his professorship because he 


GALVANI, VOLTA, AND THE CELL 57 

would not swear allegiance to the Cisalpine Republic, 
and though restored, could not return, but died in re¬ 
tirement. His name remains enshrined in the term 
galvanism , and its derivatives. 

Though he did not greatly profit from his own ex¬ 
periments, he furnished to another the means for a 
great discovery and invention—no less than anew 
source of electricity , and a source far superior to the old 
electrical machines. This other was Alessandro Volta, 
also an Italian, and a native of Como, the birthplace 
of the two Plinys. Volta was a professor of physics, 
but had travelled widely and formed friendships with 
many distinguished men of science. He had written 
on the theory of electricity, adopting with some change 
the single-fluid theory of Franklin, and suggesting 
that electricity might be produced in other ways than 
by friction, such as in chemical action, by evaporation, 
melting, burning, and mixing. About 1774, or a little 
earlier, he betook himself to experiments, and in the 
next year described an invention called the “ Electroph- 
orus ” or electricity-bearer. 

This is a resinous cake, which has been melted and 
permitted to set or harden in a metallic dish. On 
this rests a metallic disk, with an insulated handle, of 
glass for instance. The resinous cake is excited neg¬ 
atively by friction with cat-skin, and then the metal 
disk is placed upon it, touched with the finger, and 
lifted, whereupon it will be found heavily charged with 
positive electricity, and will give off sparks. But 
meanwhile the resinous cake retains its charge, and 
will induce a second charge in the metallic plate. 
Rubbing electrifies the resin negatively. The disk 
being applied, its positive electricity is attracted to 


58 


GALVANI, VOLTA, AND THE CELL 


the lower surface, its negative repelled to the upper. 
The finger touch conveys away this negative elec¬ 
tricity, and the disk retains only the positive. 

This can be repeated again and again. The elec¬ 
tricity in the electrophorus is believed to come from 
the force exerted in pulling or lifting the disk with its 
positive charge from the resin with its negative charge. 

But each time the finger must touch it before it 
is lifted, for this carries off the negative charge, 



The “Electrophorus.” 


leaving the positive to be retained by the induction of 
the negative cake. Perhaps this will be best under¬ 
stood by imagining the two kinds of electricity on 
each side of the metallic plate, and the negative to 
be allowed to escape from the upper side through 
the finger and body to the ground. 

This was a most convenient little apparatus, giving a 






GALYANI, YOLTA, AND THE CELL 


59 


strong charge that could be again and again repeated 
without again rubbing the resinous cake until its 
influence had slowly passed away. Yolta spent some 
time in improving this apparatus, and likewise gave 
his attention to various ways of storing electricity in 
condensers, and to an electric balance for the measure¬ 
ment of electricity. He separated electrified plates, 
one of which was hung at the end of a beam, by 
weights put into a pan at the other—which is de¬ 
clared by the “ Encyclopedia Britannica ” to be the 
first electrometer. For in this balance electric resist¬ 
ance was measured against weight , and the same 
measurement could be made by others with other 
balances. Other of his studies related to the dis¬ 
charge of electricity through points and flames. 

Yolta was much interested by the experiments of 
Galvani and repeated them ; but soon he came to 
disagree with Galvani’s explanation. He believed 
the electricity to be derived, not from the animal 
tissues or nerves, but from the metals used in the ex¬ 
periment, and to come from their contact alone. To 
prove this, he devised very delicate tests. His instru¬ 
ment was called a condensing electroscope. 

An ordinary electroscope (or electricity viewer, as 
the Greek words may be translated) consisted of two 
pith-balls or strips of gold leaf, hung from a conduct¬ 
ing wire and put into a glass jar so that the air cur¬ 
rents may be kept away. An electric current or 
charge makes these both negative or positive, and 
they stand apart repelling one another. 

Yolta added to the top of the wire a flat plate of 
metal, covered with a waxed silk cover and applied a 
second plate to the cover, the second having an in- 


60 GALVAKI, VOLTA, AND THE CELL 

sulating handle. When this second plate was elec¬ 
trified even in very slight degree, it accumulated the 

charge precisely as a Leyden 
jar would, for the finger 
was placed on the lower 
plate to discharge the nega¬ 
tive electricity. Then the 
top plate was lifted leaving 
the lower plate’s electricity 
free, and at once the leaves 
or balls of the electroscope 
were repelled. 

This instrument was one 
hundred and twenty times 
more sensitive than the sim¬ 
ple electroscope. It is, as 
the reader will see, a com¬ 
bination of the Leyden jar or condenser principle with 
the principle that like electricities repel one another. 

Using this sensitive test, Volta put together various 
metals, and held them against his condenser electro¬ 
scope. He detected electricity in the combined 
metals, but also found out that the frogs’ legs were, 
as an electroscope, much more delicate than his con¬ 
denser electroscope, being affected when that instru¬ 
ment would not indicate any electric action whatever. 

Having perfected his tests, Volta was able to com¬ 
pare results, and found the best results came when 
different metals were in contact, especially if used 
with salty or acid solutions. lie used these solutions 
because it had been shown that they helped to get 
good results with conductors, insuring closer contact. 
But from the use of the acid solutions with metals 














GALYANI, YOLTA, AND THE CELL 


61 


they would act upon chemically came a most impor¬ 
tant discovery and invention. This is the well-kown 
Yoltaic Battery or Pile — a device that was to cause 
enormous advances in electric science and the arts 
coming from it. As Yolta described it in a letter 
read before the Boyal Society 
in June, 1800, it consisted of 
“ several dozen disks of copper, 
brass or silver, and an equal num¬ 
ber of disks of tin or zinc, of the 
same size.” Zinc and copper al¬ 
ternately are usually chosen. 

Between each pair, is a cloth 
disk dampened with salty water, 
slightly smaller, forming a pile 
or column. First copper, then 
zinc, then cloth, and so on, being 
careful to complete the pile with 

the metal disk different from that 
, . , , Volta’s Battery or 

which began it. Pile: 

This pile was then enclosed in ..Consisting alternately of 

1 disks of copper, zinc, and cloth 

a little frame of glass pillars, a re P eated - 
wire attached to the top and another to the bottom 
disk, and electricity was continuously produced as 
soon as a conductor joined the two wires. It was the 
first means of producing a continued flow of electricity. 
The force of this current was less, but its quantity was 
enormously greater than that of the electric machines 
working by friction or induction. To compare the 
flow with the flow of water, it is like water 
flowing slowly in a big pipe compared to water 
flowing quickly in a small pipe. The latter is more 
forceful though less in quantity. The voltaic pile 











62 


GALVANI, VOLTA, AND THE CELL 


gave more electricity in a less forceful way; and, 
besides, it proved that what was known as galvanism 
was only electricity produced by different means. 
Volta made a number of improvements in his appa¬ 
ratus, and was engaged in the controversy that took 
place between those who thought the electricity came 
from the mere contact of the dissimilar metals, and 
those who believed it came from the chemical action 
of the solution — as is now generally accepted. The 
discussion of this question was said to have caused 
enough ink to flow “ to float the Navy of Great 
Britain” —though one would think less use of ink and 
more use of the chemical solutions would soonest have 
settled the great dispute. 

The voltaic pile was capable of improvement as 
soon as it was understood. It was troublesome to 
dampen the disks of cloth, and they soon dried. Con¬ 
sequently ingenious workers, including Volta himself, 
used the same principle to build better apparatus. 
He made a number of separate piles, connecting top 
disks and bottom disks by conductors ; this prevented 
the weight of the disks from squeezing the cloth dry 
so quickly, or from making the moisture run down the 
sides. Then he devised another apparatus, consisting 
of cups to hold the acid-water solution while the pairs 
of metal plates were set into them. Each copper plate 
was soldered to the zinc plate in the next cup, the 
conducting wires being soldered to the first copper and 
the last zinc. This made a true electric battery. He 
called it a “ crown of cups,” since he placed them in a 
ring so as to bring the two ends of the series near one 
another. 

But in order to prevent the action of the battery 


63 


GALVANI, VOLTA, AND THE CELL 

when not in use, it was not convenient to lift the 
metal pairs separately out of the solutions, and so 
means were adopted for fastening them to a single 
support, such as a bar of wood. This was invented 
by Dr. Wollaston, who also devised a way of bending 
the copper plates in U-form, hanging each zinc plate 
into the space between. This made a larger surface 
over which there was action, and thus the cells were 
more effective. Others brought about the same im¬ 
provement by coiling the plates into cylinder form, 
thus making room for more surface in the same size 
cell. 

Another method of changing the action of the cells 
is by connecting them differently. It will be seen that 
all the zincs, and all the coppers must be connected, but 
this can be done in two ways: We may connect all 
the zincs together, then all the coppers together, and 
afterward may connect the united zincs to the united 
coppers; or, secondly, we may connect a zinc and 
copper, then another zinc and copper, and so on, and 
then connect these couples. Here are the two ways : 
Z-fZ+Z+Z-fC-j-C-fC+C and Z-bC+Z+C-j-Z+C 
-f-Z-f 0. Now, if a wire were to be run, in each group, 
from the first Z to the last C, we should have the two 
kinds of cell connection. The first sort is known as 
multiple-connection, the second as series-connection. 

The effects of the two connections vary. If we 
compare the flow of electricity to the flow of water, 
we shall see that series-connection is like running 
water through a long narrow channel, while multiple- 
connection is like running it. through a broader and 
shorter channel, or through a number of parallel 
channels. In the first case the water meets more 


64 GALVANI, VOLTA, AND THE CELL 

friction, or resistance, but will (for a given pressure of 
water) flow with more velocity. In the second case, 
the water meets less friction, and flows with less 
velocity. But the series-connection gives a stronger 
current in less amount; the multiple gives a weaker 
current in larger amount. 



Voltaic Cells Arranged in Multiple-Connection. 



Voltaic Cells Arranged in Series-Connection. 


Or we may say that connecting all the zincs to¬ 
gether adds them —makes them equal to one big zinc 
plate the sum of them all; and connecting all the 
copper plates has a similar effect. Thus, small cells 
connected in multiple become like one large cell. 

Of course, as with the water, we cannot have both 
more and stronger electricity-action, any more than 
we can with the same mill-stream run a bigger mill 
faster with the same amount of water-current. We 
can let the water run a row of little wheels, or turn 
one big wheel more slowly, as we may choose. 

It is important to understand this because the rule 
applies all through the whole science and art of 

























































GALVANI, VOLTA, AND THE CELL 65 

electricity — the idea being the same as is expressed 
in the old proverb — “You cannot eat your cake, and 
have it too.” However we may connect our wires, 
we shall be forced to choose between more or less, 
stronger or weaker — as in mechanics we must sacri¬ 
fice power to get speed, or speed to get power. And 
electricity, after all, is only another example of me¬ 
chanics, action taking place subject to the same laws. 

There are still other ways of connecting the cells, 
by combining these two main systems. Thus we may 
connect two sets of cells in series, and then connect 
the sets in multiple; or we may connect sets in 
multiple, and then connect these multiple-sets in 
series. To diagram these we may use letters as before : 
z+clz+c re P r esents two series-connections, and these 
may each be treated like a cell and joined in multiple. 
While representing multiple-connection, 

may be joined in series. The question as to what 
kind of connection is made may be decided by follow¬ 
ing the imagined course of current. To proceed 
through both elements of a cell and then through both 
of another cell, is to proceed in series; to proceed 
through one element of all cells, and then through 
the other element of all, is to proceed in multiple. 

Where the two ways are combined, consider each 
group separately, and remember that the amount and 
the pressure of electricity are governed by the original 
strength of the current caused by the action in the 
batteries as modified by the resistance of the work it 
has to do by passing along the conductors — in which 
must be included everything affected by the current, 
the plates, the solution, the connections, and the con¬ 
ducting wire. 


66 


GALVANI, VOLTA, AND THE CELL 


It is impossible here to give even in briefest form 
all the different modifications of the voltaic cell. 
They are based upon the same general principles, and 
can be understood if these are borne in mind. As 
better means of bringing about the effects were in¬ 
vented, we shall speak briefly of their principles, and 
of their inventors. 


CHAPTER VII 


THE PIONEERS OF THE SCIENCE 

By means of the voltaic cell it became possible to 
make electrical experiments on a large scale. Though 
the early batteries, like all early forms of apparatus, 
were in certain ways crude, and though such batteries 
soon ran down in strength, yet they could for a short 
time be made to yield large amounts of electricity, 
or electricity in continued currents. Thus we reach 
an era in the science — the era when current electricity 
could be used in experimental work. 

One of the very earliest to profit by the new source 
of electricity was Sir Humphrey Davy. Born in 
Cornwall, England, two years after the Declaration 
of Independence, son of a wood-carver, he is said to 
have been noted in his youth for nothing except his 
“ retentive memory, facility in versification, and skill 
in story-telling.” So the Britannica declares, ap¬ 
parently without suspecting that these are the very 
qualities to make a great investigator — remembering, 
constructing, and imagining. Davy became appren¬ 
ticed to an apothecary and doctor, and was studious 
in educating himself. When nineteen he was inter¬ 
ested in chemistry, and scared his household by garret 
explosions. 

He was lucky enough to be noticed by appreciative 
men, and was engaged to take charge of a pneumatic 
medical institution — whatever that may be ! At all 
events, it was an employment that helped him to study 

67 


68 THE PIONEERS OF THE SCIENCE 

/ 

chemistry and physics. He found out that the mineral 
silica was in the stems of reeds, corn and grasses; dis¬ 
covered in 1799 that nitrous oxide gas (“laughing 
gas ”) would intoxicate; and tried to find out what 
“ heat ” was, by causing pieces of ice rubbed together 
in a vacuum to produce heat. 

His first book of “ Researches ” caused him to be 
recommended as a lecturer on chemistry to the “ Royal 
Institution,” recently established in London. He be¬ 
came professor of chemistry in 1802, attracting great 
audiences by his brilliant lectures and ingenious experi¬ 
ments. Though ungainly and awkward in movement 
he was “ animated, clear and impressive ” in speech, 
and soon became very popular in the city, and also 
with the management of the Royal Institution. 

The members of this body put under Davy’s control 
enormous voltaic batteries, with which he could make 
most helpful experiments. 

First of the discoveries he announced was the mak¬ 
ing of a voltaic battery with one plate of metal, and 
two fluids. There followed a long list of brilliant 
papers, hardly one of which failed to “ announce some 
new and important fact, or elucidate some principle.” 
But especially he explained that both “electrical and 
chemical attractions are produced by the same cause, 
acting in one case on the particles in the other on the 
masses.” Decomposing certain alkalis by the electric 
current he discovered in 1807 sodium and potassium 
and three other new metals ; and later he carried on 
extensive chemical researches in electro-chemistry, 
showing that chemists were to find in the electric cur¬ 
rent a marvellous new assistant. This use of the 
electric current had been made in the year 1800 by 


THE PIONEERS OF THE SCIENCE 


69 


Nicholson and Carlisle, two English experimenters, 
who decomposed water into oxygen and hydrogen ; but 
Davy had been able to systematize the work and dis¬ 
cover its laws, and thus to make the beginning of a 
new science and art. 

Likewise in 1802, Davy, by sending the electric cur¬ 
rent through a circuit ending in two pieces of willow 
charcoal — carbons — had shown that a brilliant arc 
of light was produced; but it was reserved for his 
helper and follower Faraday, to discover the cause and 
the laws of this brilliant light, and thus to make it useful. 

About 1808, the batteries with which Davy had 
done so much were worn out, and in July a few mem¬ 
bers of the Royal Institution took up a subscription 
that furnished him with an enormously powerful new 
battery of 2,000 plates. With this battery he obtained 
intense currents, and showed the arch of light — the 
u carbon voltaic arc ” — in great brilliancy and beauty. 
He also noted the intense heat of this electric flame, 
finding that few substances could resist it. But strik¬ 
ing as were these experiments, they were for the most 
part only doing on a different scale what had already 
been done by the use of smaller batteries, or by means 
of electric-machine currents. 

But Davy’s experiments and researches bore more 
especially upon the chemical side of science, and, to 
the end of his life, in 1829, he never ceased to make 
useful discoveries and inventions, and to write on 
scientific or literary subjects. One of his last pieces 
of work was a study of the “ Electricity of the 
Torpedo ” (meaning the fish, of course). 

Davy’s greatest services were to electro-chemistry, 
but he also did. much to prepare the way for his sue- 


70 


THE PIONEERS OF THE SCIENCE 


cessor at the Royal Institution, Michael Faraday, by 
attracting the attention of the public and by creating 
interest in scientific work. 

Meanwhile, there were workers in other branches 
of electric science who were likewise preparing the 
road for their successors. In 1803, it is said that a 
French experimenter, M. Carpue, published certain in¬ 
vestigations on the curative effects of the electric cur¬ 
rent ; but the applications of electricity to medicine 
had no wide development until some years afterward, 
when the discoveries of Faraday had given the science 
a practical apparatus. 

About 1805 an Italian pupil of Volta named Brug- 
natelli, carried further some experiments made a few 
years earlier, and succeeded in causing the electric 
current to deposit a plating of gold upon two silver 
medals. It was not the first time this action of the 
current had been observed, but seems to be the first 
practical use of the power of electro-plating, and 
therefore the true beginning of a process that has been 
developed since in so many useful applications. 

Indeed, after a certain process has been developed, 
we may almost always find that, in some cruder form, 
it has existed for a number of years with its possibili¬ 
ties unrecognized. And this is peculiarly true of 
electricity. As we read the records, we shall find in 
these early years of the nineteenth century, and be¬ 
fore, the germs of the whole science of electricity. 
One or another experimenter in his laboratory reaches 
a result that, if it had been keenly followed up, might 
have led to results that in fact were not reached for 
many years thereafter. 

Davy’s production of the electric-arc is an excellent 



Portrait of President Roosevelt Telegraphed by 
Korn System (See also page 303) 























































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♦ 

































THE PIONEEKS OF THE SCIENCE 


71 


example. But even where the possibilities of a dis¬ 
covery are vaguely seen, the practical working out of 
its applications is a matter dependent upon many 
elements not yet in right condition. Davy, for in¬ 
stance, could not foresee how electric currents might 
become commercially cheapened in cost, so that the 
effects of his enormous battery might be secured from 
the power of a small waterfall or a steam engine. 

The telegraph was also foreshadowed long before it 
became a practicality. Lesage, of Geneva is said to 
have practically applied the idea of using frictional 
electricity in sending messages as early as 1774 ; and, 
in 1802, the fact that a current would move a compass- 
needle was observed by Komagnosi, according to Elihu 
Thomson, but no application was made for many 
years. In 1809, a still further step toward telegraph¬ 
ing was taken by Sommering, a German, who is 
credited three years later with using a telegraph 
made of thirty-five separate wires each connected to a 
point projecting upward through the bottom of a glass 
reservoir containing acidulated water. When a cur¬ 
rent was sent through any wire, gas was seen to form 
in bubbles on one of the points in the water. An 
American, Dr. Coxe, of Philadelphia, described a 
similar telegraph about the same time. 

But all these inventions were attempts to follow up 
paths that were not in the true line of progress, and 
are mentioned here only to show the reader how many 
developments of electric science are attempted, in 
seeking for the true path of improvement and success. 
We cannot mention even a tenth part of them, but 
must select only the more striking and more fruitful 
discoveries and inventions. 


72 


THE PIONEEES OF THE SCIENCE 


Passing over, therefore, the first attempts at a 
battery that would store up electric energy, the first 
use of the electric spark as a fuse to fire explosives, 
and the so-called “ dry-pile ” — a voltaic pile supposed 
to act by mere contact of metals, but really influenced 
by moisture taken up from the air, we shall next ex¬ 
amine the experiments of Oersted, for these proved to 
mark an era in the science. 

Hans Christian Oersted was a Dane, son of an 
apothecary, and was born in 1777. Like Davy, he 
began at an early age to experiment in chemistry and 
physics, and he was graduated at the University of 
Copenhagen. About 1800 he became interested in 
galvanism and electricity, and after several years’ 
travel lectured on the subject, being appointed pro¬ 
fessor of natural philosophy. 

He published papers showing the identity of chem¬ 
ical and electrical action, and upon various subjects 
tending to make science popular, and was much aided 
by the friendship of scientific men, and by member¬ 
ship in the learned societies of Europe and England. 
Oersted was honoured by a great national jubilee in 
1850, and died in 1851. 

His discoveries were numerous, including a proof of 
the existence of the metal aluminum, but in electric 
science he deserves especial fame as the one who 
proved the identity of electricity and magnetism. He 
produced magnetism by using the electric current, 
lie was led to this discovery by having noticed that 
the passage of the electric current near a magnetized 
needle caused it to turn, and by experiment found 
that the needle placed itself at right angles to a 
plane through the current and the needle center — or 


THE PIONEERS OF THE SCIENCE 


73 


crosswise to the current. Oersted is believed to have 
supposed electricity might be a form of magnetism; 
but by the investigations of the French philosopher, 
Ampere, who analyzed and systematized Oersted’s 
experiments, it was made probable that magnetism 
might rather be regarded as a form of electric action. 

In 1S20, the year following Oersted’s discovery, 
Ampere was able to declare the existence of many 




Oersted’s Discovery of Magnetic Deflection 

Above the needle, the current turns the needle one way ; below it the other way. 

laws governing the action of electric currents and 
their action upon one another and upon magnets. 
He thus became the founder of the science of electro¬ 
dynamics, or electricity acting as a force, being the 
first to declare the laws that explained and the prin¬ 
ciples that governed the electric action of currents. 

Ampere was a most precocious boy, born in Lyons 
in 1775. He said in later life that at eighteen he knew 
all the mathematics he ever learned; but besides his 







74 


THE PIONEERS OF THE SCIENCE 


skill in this one branch, he seemed to have a general 
thirst for knowledge, reading the whole encyclopedia 
through. Ampere’s father was executed by the revo¬ 
lutionists in 1793, and the son was thereby so affected 
as to remain for over a year in almost a stupor. From 
this he was aroused by a treatise on botany that 
awakened his interest, and restored his love of 
knowledge. In 1801 he became a professor of 
physics, then of mathematics, and four years later be¬ 
came attached to the Polytechnic School in Paris. 

Hearing, in September, 1820, of Oersted’s discovery 
about the magnetic needle, within a week he presented 
a complete explanation, and new discoveries showing 
that the currents in wires attract or repel one another 
as magnets do, but tending to arrange themselves so 
that their currents will flow in the same direction. In 
1821, he suggested an electric telegraph with a sepa¬ 
rate wire for each letter. He died in 183G. 

His expression of the law governing the deflection 
of the needle is very simple. Supposing a person to 
be lying in the direction of any current, so it flows 
from feet to head, and to face the needle, Ampere 
stated that the north-pole of a magnetic needle always 
turns to the left until the needle lies across the cur¬ 
rent. The rule is stated in Guillemin’s “Electricity,” 
probably by the editor, Silvanus Thompson, as fol¬ 
lows : “ When the current flows from South to North 
over the needle, the needle’s north pole turns West” 
And the reader is told that the initials of the four 
italicized words spell s-n-o-w, by which means the law 
is readily recalled. Of course, if the current flows 
Sot/th to North under the needle it turns to the East. 

The importance of this discovery lies in the fact 


THE PIONEERS OF THE SCIENCE 


75 


that it offers a simple means for determining the ex¬ 
istence and direction of the current in any conductor, 
and also brought electrified conductors and magnets 
under one classification. The Britannica declares, 
that except Faraday’s later discovery of the laws of 
induction of electric currents, “ no advance in the 
science of electricity can compare for completeness 
and brilliancy with the work of Ampere.” 


CHAPTER VIII 


FIRST ELECTRIC MOTORS, AND THERMO¬ 
ELECTRICITY 

Ampere tried the experiment of coiling a conduct¬ 
ing wire into a spiral or helix, and found that when 
electrified such a coil had the properties of a magnet; 
and that a straight bar of soft iron is drawn into the 
middle of the coil, there becoming a magnet with a 
pole at each end, was the discovery of Arago, who 
carried Ampere’s experiments further. Davy also 
made the same discovery independently in the same 
year, 1820. 

The life of Arago, which he himself has written 
with French humour and vivacity, is most dramatic 
and exciting. Born in 1786, he longed to be a soldier, 
and studied hard to fit himself for the Polytechnic 
school. He read eagerly, bearing in mind D’Alem¬ 
bert’s maxim, “ Go on, and the light will come to } 7 ou,” 
and was admitted in 1803, meaning to fit himself for 
the artillery. But in 1804 he became secretary to the 
Observatory at Paris, and thus met many scientific 
men. He was engaged about 1806 in measuring the 
meridian that formed the basis of the metric system, 
and met with most exciting adventures among the 
Spanish mountaineers, for he was thought to be a spy. 
After an imprisonment he escaped, fled to Algiers, 
and then disguised sailed for Marseilles. Captured by 
corsairs, he was rescued from a second imprisonment 

76 


FIRST ELECTRIC MOTORS 


77 


only after a long time, and even after this met with a 
whole Odyssey of adventures in his attempts to carry 
the record of his survey to Paris. 

He was congratulated by the great Humboldt upon 
his safe return, and became a professor at the Poly¬ 
technic, a member of the French Institute, and one of 
the astronomers at the Royal Observatory. He was a 
lecturer noted for brilliancy, a writer of great clear¬ 
ness and force, and a patriot not without power to do 
service to his native land. 

He visited England more than once, and made warm 
friends among the most prominent scientific men. 
His political life is quite as interesting and exciting as 
his scholastic, but cannot be here entered upon, even 
in the briefest summary. 

His researches in electricity and magnetism were 
most important. He made a study of the effect of 
various non-iron substances upon the magnetic needle, 
and found that when it was set swinging above various 
materials — as ice, glass, copper — the needle swung 
less long and less widely as it was brought nearer the 
surface. This effect is known as the “ damping ” of 
the needle. 

«• 

Then he tried revolving the substances near the 
needle, and made a discovery that proved most im¬ 
portant. Revolving a copper plate below the needle, 
he soon found that the needle began to spin. This 
was an astonishing and unexpected result, and was 
not fully explained until the investigations of Faraday 
in England some years later. Arago, as before noted, 
also was the first to magnetize steel by means of the 
electric current. 

He discovered, first, that an electrified wire attracted 


78 


FIRST ELECTRIC MOTORS 


iron filings ; then, that steel needles or bars, so at¬ 
tracted, retained magnetism ; then, that these were 
best magnetized when the wire had been coiled 
spirally, and the bar put inside the coils. The coil, or 
helix, was first used by Ampere, and the properties 
of this helix or solenoid , as it is called, from a word 
meaning tube-like, were more exhaustively studied by 
Arago. 

It is difficult to keep events in their right order 
during the busy years from 1820 to 1830, for it was a 



time of many investigators working along similar 
lines, reporting the results achieved to one another, 
and repeating with changes the various experiments 
made. The general advance in the understanding of 
the laws of electric currents, of batteries, of conduc¬ 
tors, and of magnets, had put into the hands of scien¬ 
tific observers the means of forming and testing 
theories, while the writings of Ampere, Arago, Davy, 
and their fellow workers put others upon the right 




FIRST ELECTRIC MOTORS 


79 


track, and saved them from repeating researches 
already made. 

About 1821, Michael Faraday, who had been ap¬ 
pointed Davy’s assistant came into especial prominence 
by his discovery that the electrical current could be 
readily converted into a continuous mechanical motion. 
Faraday was born in 1791, the son of a blacksmith, 
and first worked as an apprentice to a bookbinder. 
He had a fondness for study, and was taken by one of 
his master’s customers to hear four lectures by Davy 
at the Royal Institution. 

The young man took notes and wrote out the sub¬ 
stance of the lectures so successfully that he was en¬ 
couraged to send them to Davy himself. 

Davy replied kindly, and later recommended Fara¬ 
day as assistant in the laboratory. This began a con¬ 
nection with the Royal Institution that continued for 
over half a century. Though Faraday’s work was 
brilliant in many departments, and especially in 
chemistry, yet in electricity and magnetism he accom¬ 
plished most, and to these subjects he devoted himself 
most completely. While in 1821 the great discovery 
of Oersted was interesting the scientific world Faraday 
happened to be present when Dr. Wollaston and 
Sir Humphrey Davy were discussing the possibility of 
making a conducting wire rotate by means of its own 
current. Oersted having shown that the current would 
move a magnetized needle, it was natural to consider 
the effect of fixing the needle while leaving the wire 
free to rotate. To the experiments of Oersted, 
Schweigger had added further facts by bending the 
wire around the needle, finding that every part of the 
electrified wire helped the motion of the needle : and 


80 


FIRST ELECTRIC MOTORS 


when the wire is bent into a hollow rectangle or a set 
of rings, the effect of the current is increased by every 
turn. In this way the current is multiplied, so to 
speak, and even a weak current produces a strong 
effect upon the needle. This device known as a “ Mul¬ 
tiplier ” at once came into use in the form of a test 



and measure for currents, being called a galvanometer. 
Of course the resistance to the current increases with 
the length of coils of wire, so the turns must be pro¬ 
portioned to the strength and amount of the current 
to be measured. 

It was in attempting to solve the problem of causing 
rotation in a conducting wire that Faraday made the 
first of all electric motors, the germ from which all 
later forms may be shown to be derived. 

Dr. Wollaston’s visit to Davy was in April, 1821, 
and in July, August and September of that } 7 ear Far¬ 
aday wrote for publication a sketch of electro-mag¬ 
netism, repeating the experiments he described. This 
led him to the discovery of a means of making the 
electric current convert itself into mechanical motion. 
His method was to suspend in a glass cylinder corked 
at each end a wire hung from a hook, and dipping 
into mercury at the bottom of the cylinder. In the 
mercury floated a bar magnet, anchored so as to stand 


















FIRST ELECTRIC MOTORS 


81 


upright. The current was passed through the wire 
down into the mercury, and then out through a wire 
extending down through the lower cork. 

The current in passing caused the magnet to move 
or rotate around the wire. As will be seen this is to 
repeat Oersted’s experiment with a fixed wire and free 
magnet. Another account says that in the early ex¬ 
periments the magnet was fixed in the cork, and that 
the wire revolved around the magnet; but in either 
case the principle is the same. 

There is also a difference of opinion as to the time 
when Wollaston’s visit was first made to the labo¬ 
ratory, but as Faraday himself acknowledges that 
Wollaston was the first to suggest the possibility of 
causing the rotation, the matter is not very important. 

In order to understand the action of Faraday’s ap¬ 
paratus it will be necessary to examine something of 
the theory by which it is explained. Up to the time 
of Oersted a magnet was thought to contain something 
they called the magnetic fluid or fluids. But when he 
had discovered that the electric current acted on the 
magnet, this belief was given up, and after Ampere 
had studied the matter a new theory was accepted. 
According to Ampere every magnetic substance was 
the seat of electric currents passing among its particles 
in all directions. When magnetized, these currents 
were brought into united action, and in the permanent 
magnet, the currents all went in parallel directions 
crosswise to the two poles. 

Then, after it had been shown that currents acted 
on one another as magnets do, the magnet became 
only a collection of currents — as if made up of many 
coils of wire each containing a moving current of elec- 


82 


FIRST ELECTRIC MOTORS 


tricity. Next, experiment showed the laws of attrac¬ 
tion and repulsion applying to moving currents, and 
they were found to be, in general, these, as Ampere 
stated them: 

1. Conductors carrying currents, if they are par¬ 
allel and the currents in the same direction, attract 
each other. If the currents are opposite, they repel. 

2. Conductors both coming together at an angle 
or both diverging, attract when carrying currents 
going in the same direction toward or from the apex 
of the angle. If the conductors carry currents in op¬ 
posite directions, they repel. 

3. A sinuous (or wavy) conductor acts like a straight 
conductor under the same conditions. 

From these laws it w r ould seem to follow that cur¬ 
rents at right angles to one another are equally re¬ 
pelled and attracted. But of course so exact a balance 
of forces would be as difficult to bring about as putting 
a bit of iron below a magnet so near that it would 
hang in air, balancing its weight against the magnet’s 
upward attraction. 

Now, if the reader will consider Faraday’s experi¬ 
ment of a wire hanging into a cup of mercury, he will 
see that at any position of the wire the attraction of 
the magnet’s currents will be exerted from one half, 
and their repulsion from the other half —as if the wire 
were a hanging magnet and another magnet were car¬ 
ried around in the direction of the current, when one 
pole of the horizontal magnet would be always re¬ 
pelling, and the other always attracting the pole of 
the magnet hung so as to bring one pole within the 
influence of the revolving magnet. 

It is necessary to understand this action, since Fara- 


FIRST ELECTRIC MOTORS 


83 


day’s crude little apparatus was most important, “em¬ 
bodying as it did,” to quote Professor E. J. Houston, 
“ practically the fundamental principles of the electric 
motor of to-day.” 

The interactions of the electric currents with one an¬ 
other and with the magnet were also observed in other 
forms. Thus, when a magnet was brought near to 
the electric arc between the carbons, it was found by 
Davy that the arch of light was drawn from its place 
between the carbons, being either attracted or repelled 
according to the laws announced by Ampere. And 
the rotating of a conductor was brought about, also 
by Davy, in a dish of mercury, the liquid answering 
to the laws just as the conducting wires, the magnets, 
the arc-light, and other electric manifestations had 
done. 

About 1823 there was discovered another new 
method of causing the electric current. First, it had 
been excited by friction, leading up to the develop¬ 
ment of the powerful electric machines, which had led 
to the discovery of electricity by induction, and to the 
electrophorus, and the Leyden jar; then it had been 
produced by the voltaic pile, leading to the electric 
voltaic cell and batteries. And now an experimenter 
named Seebeck found a new way to obtain electric 
currents. 

As in the case of frictional electricity there were 
certain ancient observations giving the hint of what 
lay concealed. Pliny told of a crystalline stone that 
when heated attracted light bodies, and there had 
been experiments made especially with the mineral 
tourmaline to investigate its property of attracting 
and repelling light substances when heated and cooled. 


84 


FIRST ELECTRIC MOTORS 


When this property was definitely connected with 
electric theories, the action was named pyro- or fire- 
electric. When the crystal was heated, poles were de¬ 
veloped that acted like those of an electrified con¬ 
ductor. 

But though many had experimented with various 
crystals showing such properties, there had been no 
striking developments. Professor Seebeck, of Berlin, 
discovered that instead of being confined to certain 
natural substances, the property of giving rise to an 
electric current when heat was applied or a change of 
temperature affected, was general among all metals, 
providing certain conditions are fulfilled. Seebeck 
found that “ when two metals of unlike crystalline 
structure and conducting power” are soldered to¬ 
gether and the junction either heated or cooled, an 
electric current flows across the junction, generally to 
the poorer conductor. Such is the statement of Pro¬ 
fessor Houston, who probably gives the law as later 
experimenters have expanded it, rather than as it was 
known to Seebeck, as it sounds very general and more 
comprehensive than it would be when announced after 
only a comparatively few experiments. 

Later modifications of the thermopile — as the 
series of connected metals is called — have not essen¬ 
tially changed the principle, and it must be remem¬ 
bered that to Seebeck the credit of the apparatus is 
due, and that to him fairly belongs the invention of 
a wholly new method for producing an electric cur¬ 
rent. Besides being an independent invention, See- 
beck’s apparatus was another link in the chain show¬ 
ing that electricity was produced by a whole set of 
causes — and thus it helped men to understand that 


FIRST ELECTRIC MOTORS 


85 


they were dealing with a state rather than with a 
substance. We shall see later how each little inven¬ 
tion based on a new.disco very brought about a change 
in the understanding of electricity, that is, in its theory 


CHAPTER IX 


THE ELECTRO MAGNET, THE MOTOR, AND 

INDUCTION 

It will be noticed that nearly all the eminent work- 
ersin the new science of electricity were “ professors,” 
being connected either with some university or similar 
learned institution. This is the case with Galvani, 
Yolta, Gray, Davy, Faraday, Arago, Ampere, Dufay, 
and others. While this may be in some degree due to 
the fact that these men had access to laboratories, li¬ 
braries, and the records of other men’s discoveries, 
yet there is another reason for their success. The 
science of electricity, as soon as it began to develop 
at all, was clearly understood only by men who could 
reason about things theoretically—that is, by using 
mental images, and by applying general laws mentally. 
This is the mathematical faculty 7 , — another form of the 
constructive imagination already spoken of, — and 
these professors were men accustomed to that difficult 
kind of reasoning. 

Electric action in or along a conductor cannot be 
seen, but must be followed mentally if practical inven¬ 
tions are to be made. The inventor has in mind a no¬ 
tion of the whole process, and then arranges real things 
to carry it out; or he notes an action that does not 
agree with his notion, and then makes guesses at the 
cause, and tries experiments until he has found the 
reason—new or old. 


86 


ELECTRO MAGNET, MOTOR, INDUCTION 87 


The next great step forward after the invention of 
the electric motor was the invention of the electro¬ 
magnet. This is due to two men at about the same 
time—Sturgeon of England and Henry of America. 
Arago had magnetized steel bars by putting them in¬ 
side glass tubes about which a spiral of wire conducted 
electricity. In 1825, William Sturgeon, who began 
life as a shoemaker’s apprentice, and, after a short time 
as a private soldier, became an investigator of electro¬ 
magnetism, made the discovery that soft iron when 
put inside the coil of wire instead of the steel bar was 
magnetic only while the current passed, losing its mag¬ 
netism when the electricity is cut off. He also noted 



Magnets—Henry’s (A). Sturgeon’s (B) 


that the introduction of the soft iron core greatly 
helped the magnetic effect of the coiled wire and cur¬ 
rent. Since the iron core could not be called a mag¬ 
net, not being permanently magnetized, Sturgeon 
called the whole combination an “ Electro-Magnet.” 
He also used the horseshoe form for the core. Thus 
Sturgeon had advanced upon Ampere’s use of a steel 
core, by using a soft iron core in the coil. 






























88 ELECTRO MAGNET, MOTOR, INDUCTION 

Professor Joseph Henry completed the invention, 
and increased its value immeasurably by remembering 
the Schweigger multiplier idea. Schweigger used the 
multiple coils to strengthen the action of the current 
upon the deflection of a needle. Henry applied the 
multiple coils to strengthening the action of the cur¬ 
rent upon the soft iron core of Sturgeon. Beginning 
with the idea of studying medicine, Henry did oc¬ 
casional writing on scientific subjects and was ap¬ 
pointed engineer to survey a road from the Hudson 
River to Lake Erie. This turned his attention to 
science, and he became in 1826 a professor of mathe¬ 
matics and physics in the Albany Academy, and the 
next year read his first paper on the “ Electro Mag¬ 
netic Apparatus.” His great improvements were the 
use of insulated (silk-wound) wire for the coils, the use 
of multiple coils, and also—an invention based on 
his own discoveries—the use of a single wire wound 
spool-fashion when using batteries in series, and the 
use of a number of separate wires, each wound around 
the magnet, when the batteries were connected in mul¬ 
tiple. The numerous coils were found to conduct the 
latter form of current more efficiently. 

Henry’s electro-magnets formed on these principles 
were enormously powerful for his time — one in 1830, 
lifting J50 pounds ; one in the following year 2,300, 
and, in 1834, one lifted 3,500 pounds. 

But before proceeding with the account of Henry’s 
researches, there are still some important steps to be 
noted in the years from 1825 to 1830. In 1826, there 
was an improvement upon Faraday’s motor in the ap¬ 
paratus of Peter Barlow, a professor in the Woolwich 
Academy of England. Barlow’s invention as pictured 


ELECTRO MAGNET, MOTOR, INDUCTION 89 

shows a flat board on which lies a permanent horse¬ 
shoe magnet. Between its poles is a little trough of 
mercury, into which dips a star-shaped wheel sus¬ 
pended on an axis, supported from a frame. Elec¬ 
tricity is conducted along the support to the wheel, 
through the mercury and back to the battery, causing 



Baklow's Invention 


the wheel to revolve. This form of motor was again 
changed by Sturgeon, who used a circular smooth 
edged copper wheel, and instead of the mercury used 
the contact of the conducting wires—one at the axis, 
the other on the edge. This was not satisfactory, the 
contacts being not always good. Both these little 
motors were only connecting links to better forms. 

In 1827 there was announced by Dr. George Ohm, 
a German professor of mathematics, born in 1781, a 
most useful law for calculating the amount of elec¬ 
tricity acting through a circuit in a given time. The 
law was' based upon the researches of others, but has 
proved so useful that its discoverer is entitled to the 
fame he has acquired by having the unit of electrical 
resistance named the “ohm.” It measures the difli- 

















90 ELECTRO MAGNET, MOTOR, INDUCTION 

culty the current meets in getting through a conduc¬ 
tor, just as friction measures the difficulty in turning 
a grindstone. Professor Houston states the value, 
roughly, of one ohm, to be “ the resistance of two 
miles of ordinary trolley wire,” or “ the resistance at 
45° Fahrenheit of one foot of No. 40 copper wire,” 
which is a little over three-thousandths of an inch in 
diameter. 

Ohm’s law is briefly this: The strength of the cur¬ 
rent equals the electro-motive force divided by the re¬ 
sistance; or to substitute the electric names: The 


amperage equals the voltage di¬ 
vided by the ohms ; and there¬ 
fore : One ampere equals one 
volt divided bv one ohm. To 

•s 

compare electricity with water 
flowing from a reservoir, the 
ampere is the unit rate of flow, 
the volt is the unit pressurecaused 
by the height of water, and the 
ohm is the unit resistance or fric¬ 
tion to the flow. The coulomb — 
another electrical unit, of amount , 



A Galvanometer would be represented by the quan¬ 
tised for the detection and meas- tity of water that would be de- 


uring of currents. 


livered in a given time under unit 


pressure and resistance. The full importance of Ohm’s 
law was not recognized until about fourteen years 
later, when the Royal Society of England awarded him 
the Copley medal. But as the complexity of appara¬ 
tus increases, the value of such helpful laws becomes 
more and more evident as they are applied to help in 
the solution of practical problems. 

















ELECTRO MAGNET, MOTOR, INDUCTION 91 

Another very important event of the year was the 
exhibition, by Professor I. F. Dana, of Columbia Col¬ 
lege, of Henry’s electro-magnet in a course of lectures 
on physics. Among Dana’s audience was the artist 
Samuel F. B. Morse, who thus first saw in operation 
the device that was to make possible the telegraph in¬ 
struments he afterward perfected. But Henry him¬ 
self saw something of the possibilities of the electro¬ 
magnet as a means of transmitting power to a distance. 
In 1828, the very next year, he suggested that by 
means of an insulated wire an electric current could be 
made to operate his great electro-magnets as far as 
sufficient current could be carried, but the develop¬ 
ment of this idea was postponed until after the tele¬ 
graph had reached a state of practicality. And this 
order of development was natural, since the conveying 
of intelligence was then even more desirable than to 
carry either power or material things. 

In 1829, Becquerel made a new voltaic battery in 
which he used two fluids instead of one. He was a 
French physicist, born in 1788, an officer of Engineers 
who became a member of the Academy of Sciences. 
His double fluid cell was made by letting each ele¬ 
ment of the battery dip into a separate fluid, instead 
of both into one. The principle was perfected by an 
English electrician, Daniell, in 1836, and Becquerel is 
here mentioned only because he was, contrary to what 
is often stated, the first to suggest the use of the sec¬ 
ond chemical to absorb the gases liberated by the or¬ 
dinary cells of zinc and carbon, though Daniell’s cell 
was the first to make the suggestion practical. 

In 1830 there was an attempt to construct an elec¬ 
tric motor on a new principle. An Italian, the Abbe 


92 ELECTRO MAGNET, MOTOR, INDUCTION 

Dal Negro, who was professor of Natural Philosophy 
in the University of Padua, hung a magnet on a 
pivot, like a pendulum, so that its lower end could 
swing while the upper end was between the poles of 
an electro-magnet. A current being sent through the 
magnet attracted the upper end to swing toward one 
pole. But as it swung, a rod tipped a little frame so 
that conducting points were dipped into mercury cups, 
and changed the direction of the current. Then the 
other pole of the electro-magnet attracted the pendu¬ 
lum top, the current was changed again, and so on. 
This method of getting motion was inferior to that 
used by Professor Henry in a little model motor still 



Professor Henry’s Motor 


preserved in Princeton University, which he devised 
in the following year. Henry hung an electro mag¬ 
net like a walking-beam or scales, and as it turned on 
its pivot caused it to dip two wires into two mercury 
cups on each side, closing a circuit first on one side, 
and then on the other. Below the ends of the hori¬ 
zontal magnet were two upright magnets, and as the 
poles of the beam magnet were changed, it was at¬ 
tracted alternately to one and the other. 

But this continual change of motion, whereby mo¬ 
tion in one direction must be stopped and then motion 



























ELECTRO MAGNET, MOTOR, INDUCTION 93 

in the opposite direction set up, is not good mechanics, 
and so these swinging motors were not developed af¬ 
ter the rotary motors were devised. 

In 1831 Faraday, whom Tyndall called “ the great¬ 
est experimental philosopher the world has ever seen,” 
made a discovery of supreme importance. Oersted 
had shown how electricity might be made to produce 
magnetism, and as a consequence the development of 
the motor began ; for the voltaic cell gave electric ac¬ 
tion, the electricity set up magnetism, and magnetism 
made and unmade could be changed into mechanical 
work. 

But Faraday was to show how magnetism could be 
changed into or made to give the electric current 
when a magnet was acted upon by mechanical motion. 
That is, he was to make it possible to convert motion 
—whether natural or artificial—into an electric cur- 
rent. This done, waterfalls, wind, steam power, ani¬ 
mal power, or human power could be turned, as one 
may say, into electricity. Professor Houston says, 
“ Faraday’s discovery should indeed be ranked in im¬ 
portance before the discovery of Oersted were it not 
dependent on Oersted’s.” 

Faraday, like others, believed in the possibility of 
getting electricity from magnetism long before it was 
done in practice. His earliest experiments were 
made with active currents, and no matter how 
strong these were, he failed to find indications of the 
induced currents he was seeking. But after many ex¬ 
periments he noted that whenever a circuit was made 
or broken, there was a slight movement of the galva¬ 
nometer needle—that is a slight induced current was 
present in the circuit placed within the influence of 


1 


94 ELECTRO MAGNET, MOTOR, INDUCTION 

the active circuit. This slight induced current ceased 
as soon as the other current was at full strength or 
had entirely ceased. Observation showing him that 
this induced current was oj>j>osite to that of the in¬ 
creasing active current, and in the same direction with 
the decreasing current. It is during this investigation 
that Faraday wrote to a friend that “he thought he 
had a good thing,” but that it might be “ a weed in¬ 
stead of a fish.” Next Faraday sought a means of 
causing the current to increase or decrease continu¬ 
ally. He caused a coil of insulated wire to approach 
to and then to recede from an active current, and 




Faraday’s Experiment in Magnetic and 
Voltaic Induction 


found this was equivalent to shutting off or turning on 
the current. An induced current was thus produced 
in the insulated coil. The next step was to use a mag¬ 
net in place of the active current, and this also pro¬ 
duced the induced current. 

The problem was solved, and it remained only to 
devise the best practical means for causing the con¬ 
tinual production of the induced currents. But Fara¬ 
day was usually content to leave minor invention to 












ELECTEO MAGNET, MOTOE, INDUCTION 95 

others, knowing that his best work was done by look¬ 
ing for new facts and new laws. 

Thus had Faraday established the principles of 
“ voltaic-electric induction,” and u magneto-electric in¬ 
duction,” as he called the action, according to whether 
the current was induced by a battery or by a magnet. 
Thus he virtually founded modern electrical in¬ 
dustries. 

Once the principle was understood it was not diffi¬ 
cult for so able an experimenter to secure the desired 
results in a number of ways. By using a large spool 
of insulated wire, hollow at the middle, and placing 
within this another spool in which was an active cur¬ 
rent from a battery, the induced currents were set up 
in the first coil whenever the second was inserted or 
withdrawn. Or, by leaving the small coil within the 
larger, and connecting or disconnecting the battery, 
the currents were induced—the inverse (opposite) when 
connection was made, and the direct (same direction) 
when it was broken. 

With induced currents Faraday was able to perform 
the same experiments (with one exception) as with 
others however produced, thus proving their identity. 
The exception was the chemical effects ; but at a later 
time he found that very rapid making or breaking 
was necessary to produce these; and the identity of 
the induced currents with those coming from ma¬ 
chines, batteries, thermopiles, and any source was es¬ 
tablished. 

Now that the principle is known, it is easy for any 
one to show the induced currents. For example, if a 
piece of insulated wire be coiled, and its two ends at¬ 
tached to a bit of iron, approaching or withdrawing a 


96 ELECTRO MAGNET, MOTOR, INDUCTION 

magnet to the iron will move a compass needle within 
the coils. 

From this discovery it was not a difficult matter to 
construct a little machine for producing electricity 
from a permanent or electro-magnet—that is to make 
the first dynamo . Faraday hung a copper disk or 
wheel upon an axle, and attached a crank for turning 
it, so as to make it revolve between the poles of a 
horseshoe magnet. Against the axle, and against the 
edge of the disk rested flat bits of copper, or brushes , 



Faraday’s Disc-Dynamo, the First Dynamo 

Ever Built 

When the copper disc A is rotated from left to right between the 
magnet-poles, currents are set up in the direction of the small 
arrows and are taken off by the curved brushes. 

to each of which was attached the end of the conduct¬ 
ing wire. Turning the disk, an electric current was 
set up in the wire—as a galvanometer showed by the 
deflection of its needle. The baby dynamo was born, 
and soon began a growth that we cannot yet with cer¬ 
tainty limit. 

As to the explanation of its action, there are 
theories, but they are not yet certainly established. 
To state them is only to give the law , not the reason 
of the dynamo’s action. In general it may be said 
















5,000 Horse-Power Dynamos, 25 Revolutions per Second, 2,200 Volt 
Current, Niagara Falls Power Co. 

Front stereograph, copyright ly Underwood and Underwood, N, Y. 

(See also page 255) 











































ELECTRO MAGNET, MOTOR, INDUCTION 97 

that by the experiment of strewing iron-filings near an 
electric current or an electro or permanent magnet, we 
find them arranging themselves in certain lines that 
have been called “lines of force.” These lines are 
taken to indicate the situation in space of the electric 
and magnetic action, and they show the electric action 
to be in circular form about electric conductors and 
about magnets. 



The Magnetic Lines of Force 


Now when these lines of force are interrupted by a 
conductor, electric currents are set up in the conduc¬ 
tor or around its surfaces. Consequently, when in 
Faraday’s little disk dynamo the disk is turned be¬ 
tween the magnet-poles, the lines of force between the 
poles are cut quickly near its edge, more slowly nearer 
its centre, and the conductor is electrified, a current 
is set up from edge to axis—and from it the conduct¬ 
ing wires make a path for the current produced. 

As to the production of the induced current, Pro¬ 
fessor Houston explains it by saying that as the live cur¬ 
rent increases , the lines of force increase in number, 
and extend outward around the conductor, thus being 
interrupted by the other conductor; while the current 






98 ELECTEO MAGNET, MOTOE, INDUCTION 


decreases , the lines of force decrease, drawing closer to 
the conductor, and are again interrupted by the other 
conductor. 

Whether this explanation exactly agrees with the 
facts or not, it is at least a right way of considering 
the action, and enables one to think clearly of it. 

In the same year of the birth of Faraday’s baby 
dynamo, Professor Henry was at work in two direc¬ 
tions that were of first importance. lie is credited by 
some authorities with the independent discovery of the 
induced currents at the same time as Faraday. We 
have described his beam-action motor, but we have 
merely mentioned his first step in telegraphy ; but the 
early attempts at telegraphy will be told of in the 
next chapters. 


CHAPTER X 


FIRST BUSINESS USES 

We have already said a word or two about Som- 
mering’s multi-wire telegraph and there were a num¬ 
ber of investigators and inventors besides, who had 
before this time made some steps toward an electric 
telegraph. These may be briefly noted in passing, but 
need not be fully described since their cruder methods 
were superseded by a better use of the same principles, 
or the use of new principles. The first idea was that 
of “sympathetic needles” that would move alike 
though at a distance from each other; but these, 
though spoken of, were not possible before the discov¬ 
ery of the action of the electric current on the mag¬ 
netic needle. In the eighteenth century the multi¬ 
wire system was thought of, and was possible. An in¬ 
teresting fact is the publication in the Scots Magazine 
of Edinburgh, in 1753 of an anonymous letter describ¬ 
ing fully the means of telegraphing through a set of 
twenty-six wires by causing each to attract a letter of 
the alphabet. The signature to this proposal was only 
the initials C. M., and many useless guesses have been 
wasted on the problem of discovering the author ; and 
in 1809 came Sommering’s bubble telegraph. In 1820, 
Oersted’s discovery made telegraphy possible, and as 
Professor Owen said, “Nothing might seem less 
promising of profit than Oersted’s painfully pursued 
experiments with his little magnets, voltaic pile, and 

99 


100 


FIKST BUSINESS USES 


bits of copper wire. Yet out of these has sprung the 
electric telegraph.” But neither Oersted nor Ampere 
ever seem to have made a telegraph line. Then came 
the Sturgeon magnet, and its improvement by Henry, 
and its application by Henry in 1831 to the giving of 
a signal at a distance. He arranged a bell so that it 
was struck by a rod, moved by an electro-magnet, and 
as is remarked in Byrn’s, “Progress of Invention in 
the Nineteenth Century,” “this may be considered the 
pioneer step of the telegraph.” But credit should also 
be given for another discovery that helped to make 
telegraph lines practicable. This was the observation 
made by AVeber, the German electrician, in 1823, that 
a bare copper wire carried through the air in Got¬ 
tingen from his house to his laboratory, needed no in¬ 
sulation beyond being kept clear. Without this help, 
the establishing of long circuits would have been most 
expensive and troublesome. 

We have already seen that Morse had heard from 
Professor Dana’s lips the properties of Henry’s mag¬ 
net. In 1829 he had gone to Europe, and on the home 
voyage in 1832 began to consider the question of the 
electric telegraph. 

But before entering upon this question, it will be 
well to say something of Morse’s earlier life. Born in 
1791 in Charlestown, Massachusetts, he entered Yale 
in 1805, and here received the instruction of Professors 
Day and Silliman in science. In 1811 Morse began 
the study of art under Washington Allston, with 
whom he went abroad, returning in 1815. From 1825 
to 1845 he was president of the National Academy of 
Design. A second visit to Europe was made in 1829, 
and upon the ship Sully , he was informed by Dr. 


FIRST BUSINESS USES 


101 


Jackson, of Boston, of Faraday’s experiments ; and 
soon after, in a discussion with fellow passengers he 
set forth the general principles of the necessary ap¬ 
paratus for a telegraphic line, and showed sketches of 
it to his companions and to the captain of the ship. 

Morse’s invention at the time of his landing, was 
comprised only in his sketches, showing an electric 
circuit, a system of “ dots or points, and spaces to 
represent numerals,” and two ways of causing the 
electricity to mark these on a ribbon of paper — one by 
chemical action, the other by moving a lever carrying 



The Peltier Cross 

A—Antimony. B—Bismuth. 


a pen or pencil. He also thought of moving the rib¬ 
bon regularly by clockwork, and of burying the con¬ 
ducting line in tubes. Soon after landing in Novem¬ 
ber, 1832, he planned and sketched the idea of carry¬ 
ing the line on posts. But his earliest model was not 
made until 1835. 

Meanwhile in 1834, in observations upon the 
thermopile, it was discovered by an investigator named 
Peltier, a retired French watchmaker, that if a current 

















102 


FIKST BUSINESS USES 


were sent through the two joined metals in one direc¬ 
tion, the junction was heated ; but that when the cur¬ 
rent was sent in the reverse direction, the junction 
was cooled. It will be seen that this bears a similarity 
to the changing of electricity to magnetism and mag¬ 
netism to electricity, in that change of temperature of 
the junction of the thermopile, produces electric 
action, and electric action produces change of temper¬ 
ature. 

Another experimenter, Lenz, succeeded in causing 
this “ Peltier effect ” to freeze water, and lower the 
temperature of its ice to twenty-four degrees Fahren¬ 
heit, or eight degrees below freezing-point. 

Between 1831 and 1834, Faraday had drawn from 
his experiments the general laws governing induced 
currents. “Nothing,” says the article in the 
Britannica, on “Electricity” (speaking of this law), 
“ in the whole history of science is more remarkable 
than the unerring sagacity which enabled Faraday to 
disentangle by purely experimental means the laws of 
such a complicated phenomenon as the induction of 
electric currents.” The general statement of the law 
is given in the same article as follows : “ Whenever 

the number of lines of force passing through a closed 
circuit is altered, there is an electro-motive force, tend¬ 
ing to drive a current through the circuit, whose 
direction is such that it would itself produce lines of 
force passing through the circuit in the opposite direc¬ 
tion.” Perhaps this can be more readily under¬ 
stood if we resort to the usual comparison of 
the electric current to a current of flowing 
water. Let us suppose a flexible tube inside which 
flows a current of water in a spiral course — thus 


FIBST BUSINESS USES 


103 


making it resemble in the lines of force the elec¬ 
tric current. Now if we bend this tube into a 
circle, and then contract the circle to a smaller one, 
there will be a tendency to inclose more spiral lines of 
force into a smaller space, and there will be an in¬ 
crease of the current rate in the same direction. Then 
if we open out the circle, there will be fewer spiral 
lines of force inclosed, and it is as if the current rate 
decreased, or there was a reverse flow of the cur- 
ren t. 

It is not meant that this is a true representation of 
what occurs, but only a sort of mental picture helping 
us to remember the Faraday law. Lenz, the French 
experimenter before mentioned, added another expres¬ 
sion of the law of induced currents, declaring that u In 
all cases of electro-magnetic induction, the induced 
currents have such a direction that their reaction 
tends to stop the motion that produces them.” 

After reading these laws, the non-expert reader will 
realize that we have been hastily going over a ver}^ 
great development in passing from the rubbed-amber 
attraction recorded by Thales to the general law of 
induction worked out by Professor Faraday. And 
yet the progress has been by successive steps, in 
which each pioneer hewed out a little clear space 
through the jungle of ignorance, and made thereby a 
road for his successors to extend still further. So 
general is the progress in these fruitful years that we 
are compelled to save space by making only the 
briefest reference to certain improvements in order 
that we may be able to dwell more at length upon the 
most important, remembering that many workers, all 
over the civilized world were busy in carrying forward 


104 


FIEST BUSINESS USES 


each form of electric apparatus, or in making new 
inquiries into the laws of electric action. 

The motor, for example, when we next take it up, 
has assumed a rather complicated form. Sturgeon s 
smooth wheel developed from Barlow’s spur-wheel, has 
been superseded by the rotary-motor of Moritz Jacobi, 
a multiplication of electro-magnets. Jacobi was a 
German who went to St. Petersburg in 1837, and be- 



Jacobi’s Rotary Motor 

came a member of the Academy of Sciences, and later, 
councilor of state. lie set up two wooden star-shaped 
frames each supporting twelve electro horseshoe mag¬ 
nets turned with poles inward (A, B). Between these 
wheel-shaped frames a turning wheel (B) carried 
straight electro-magnets, so that their poles were 
brought opposite those on the outer frames as the wheel 
turned. But, in turning, the poles of the inner magnets 
were changed as they came opposite the outer ones. 
This was done by commutators , disks (A) set on an axis, 
and so connected as to bring the electric current at one 

















FIEST BUSINESS USES 


105 


part of the turn to one magnet, and then to another. 
Thus the inner magnets were first attracted, and then 
by a change of polarity, repelled by the outer mag¬ 
nets. The result was to keep the inner wheel spin¬ 
ning. At the end of its axis was a gear-wheel ( r ) to 
which machinery could be attached {/). 

Improvement in the dynamo also had been made. 
Pixii, a French inventor, revolved a large permanent 
horseshoe magnet vertically beneath a fixed electro¬ 
magnet—thus inducing 
alternating currents in 
its coils as the turning 
magnet was brought 
near and then moved 
away. A commutator 
on the axis distributed 
the two currents to 
separated wires, thus 
making each contin¬ 
uous. It will be well 
to say a word of ex¬ 
planation about the 
commutator principle, 
as it is used in all 
cases of the kind. By 
placing on the turning 
axis a disk divided by 
insulating divisions into 
different conducting portions, these portions can be made 
to rub against conducting springs at different times. 
Thus, suppose an axis to end in a branched form like an 
upturned letter We could arrange two springs so as 
to touch different branches of the ^ at different times. 



Pixii’s Dynamo ( 1832 ) 

(Note Commutator A.) 































106 


FIRST BUSINESS USES 


Then when a positive current was passing it would 
go to one spring so long as it was in contact. As the 
axis turned further, this positive spring would leave 
its branch, and the other branch would touch the 
negative spring while the negative current was pass¬ 
ing Then if conducting wires ran from each spring 
and were connected into a circuit, the current would 
always be sent in the same direction, since each end 
of the wire would be in contact with the axis only 
while its own kind or direction of current was coming. 



Diagram of Two-Part Commutator 

The commutator C mounted on a core of hard rubber insulation 
is attached to the axis of the armature, which revolves be¬ 
tween the magnet-poles in the direction of the arrow. The 
brushes B B of spring brass, connected with the external cir¬ 
cuit, collect the current from the commutator. 

A split ring on an axis might be so arranged as to act 
in the same way, or two studs projecting—or a dozen 
other devices. This is the “ changer ” of currents, or 
commutator—a very essential and ingenious device, 
said to have been suggested by Ampere, adopted by 
Pixii, and improved by Sturgeon. 


FIRST BUSINESS USES 


107 


But to return to the motor. An improvement 
in Pixii’s machine was devised by Joseph Saxton, an 
American inventor who rotated the electromagnet 

O 

instead of the heavier permanent magnet, putting the 
latter horizontally ; and his device was bettered by 
Clarke, who, leaving the permanent magnet vertical, 
revolved the electro magnet in front of the side of the 
poles on an axis going between them—which made the 
machine compact. lie also wound the two poles of the 
electro-magnet oppositely, thus delivering an alternat¬ 
ing current that the commutator made continuous or 
left alternating at will. This machine gave currents 
of more force than could be given by any single kind 
of batteries. The principle of Clarke’s machine was 
some years later applied to electric lighting, as will 
be seen. 

Within a year or two after this improvement of 
motors began, a Vermont blacksmith, named Thomas 
Davenport, invented a motor upon the excellent prin¬ 
ciple of revolving electro-magnets in the form of a 
cross within the circumference of two permanent mag¬ 
nets, each bent in a half circle and set in a ring form. 
This motor was so successful that it was used to 
operate a small circular railway at Springfield, Massa¬ 
chusetts, in 1835, and a few years later to run a print¬ 
ing press whereon was printed a little paper called the 
Electro-Magnet. Another American motor, invented 
by Ritchie, rotated the armature on an axis set within 
the U of the permanent magnet, as if a heavy-topped 
T were set into the U. But there is no need to go 
into all the modifications of these motors. All sorts 
of combinations were made, and gradually the better 
ones were retained and improved while the others 


108 


FIRST BUSINESS USES 


were abandoned. It is better to give some attention 
to the attempts to make these motors useful. Jacobi’s 
motor was considered promising enough by the Em¬ 
peror of Russia to induce him to spare the money 
for the construction of an electric boat, to be run by 
a bigger form of the motor. The boat was built and 



Davenport’s Motor 


fitted with paddle wheels driven by the motor. It car¬ 
ried ten or twelve persons, and at times it ran for a 
whole day without accident. But at other times 
Jacobi was less lucky, and break-downs occurred that 
were difficult to repair. However, the electric boat 
went three or four miles an hour, and developed a fair 
amount of power from the battery of sixty-four cells. 

On land, it will be remembered that Davenport had 






























































FIEST BUSINESS USES 


109 


already run his locomotive, driven also by voltaic bat¬ 
teries actuating his form of motor; and thus there 
were before 1810 distinct beginnings of electric loco¬ 
motion on land and sea, but the cost of even the 
cheapest batteries was so great that the machines re¬ 
mained no more than the experimental triumphs con¬ 
cerning which the skeptical might ask cui bonof — 
“ What is the use ? ”—not always receiving so clever a 
reply as Franklin gave to a similar objection when he 
asked in return : “ What is the use of a baby ? ” 

And truly these electric “ babies ” were being born 
at a rate that almost defies even a census of them 
within any fair space. The science was developing 
into specialties, and each of these was being pursued 
by an industrious group of workers; while at the same 
time those whose breadth of view enabled them to 
take in the whole field or a large part of it, were an¬ 
nouncing the laws that made the work of specialists 
directed by right principles, and truly scientific. Far¬ 
aday, whose work was invariably productive, had 
been experimenting with the electrical decomposition 
of chemicals by means of the apparatus now known 
as the “voltameter.” Beginning in 1831, he made 
elaborate investigations that continued for nine or ten 
years and resulted in the discovery and declaration of 
the laws governing “ electrolysis ”—laws that have 
stood the test of time, but the reasons for which are 
not yet completely understood. 

As these laws are fundamental, and aid us in un¬ 
derstanding the progress of the science, they may be 
given here, although they may not be entirely under¬ 
stood in all their applications, until later inventions 
have been considered. 


110 


FIRST BUSINESS USES 


The general laws were announced in 1833, and are 
as follows : First at all points of a circuit, 1 the amount 
of chemical action is equal. Second, the amount of an 
“ ion ” liberated at an electrode in a given time is pro¬ 
portional to the strength of the current. Third, the 
amount of an ion liberated at an electrode in one sec¬ 
ond is equal to the strength of the current multiplied 
by the “ electro chemical equivalent ” of the ion. 

The italicized words must be explained, and so must 
the action of a voltameter, and the reason for the 
name. First, a voltameter includes a means for pass¬ 
ing an electric current through a conducting liquid, 
and for collecting the resulting products. It thus 
measures the strength of an electric current bv meas- 
uring the amount of chemical decomposition it pro¬ 
duces. The current from a battery is conducted by a 
wire into the liquid, and leaves by another which com¬ 
pletes the circuit. Then the end of each wire is led 
into a glass test tube, or similar receptacle, inverted 
over it. By the use of such an apparatus, as has bden 
said, Carlisle and Nicholson in 1800 decomposed water 
into hydrogen and oxygen. Later it was found that 
other liquids—such as dilute acids and solutions of 
salts of metals, could be likewise separated into their 
elements, and in every case the same elements always 
were liberated at the same pole. Faraday proposed 
names for the process and its results. Electrolysis is 
the process. The liquid is the electrolyte , and the 
wires electrodes. The endings are all Greek—meaning 
as follows : lysis , separation ; lyte, thing separated ; 

1 Professor Houston suggests that the circuit meant is a simple or series 
circuit, since the law as stated does not strictly hold for a multiple- 
series or series-multiple circuit. 


FIRST BUSINESS USES 


111 


odes, paths. Then to distinguish the two poles, he 
called the positive, the anode, or to-path; the nega¬ 
tive, the kathodey or frorn-path. 

Then, in order to explain the action, various 
theories had been made as to how the elements sepa¬ 
rated—a matter in dispute; but generally speaking it 
was thought that the atoms of one kind were set free 
more or less from their chemical bonds to the other 
kind, and wandered about. Faraday called these sepa¬ 
rated atoms, ionSy meaning the go-ers or wanderers. 
Then to distinguish them by their goals, he named 
them “anions ” and “ kathions.” 

This will explain his laws as meaning that the ac¬ 
tion of the current is the same all through its course ; 
that multiplying the current multiplies the action 
to the same extent; and that the ions liberated are 
always in proportion to their “chemical-electro-equiv¬ 
alent”—which signifies its fixed replacing power in 
combination with other elements. This is determined, 
and given in tables for use. 

When it was known that the result of electrolysis 
for a given time, in a given solution with a given cur¬ 
rent was always the same, it became possible to 
measure currents as compared to one another. A 
current of twice the strength—or voltage—would do 
twice the decomposing in the same time, and this 
could be measured b \ weight. Hence the name “ volt¬ 
ameter ” or volt-measurer, for the apparatus. 

This was another great step toward making the 
science of electricity an exact science, instead of guess¬ 
work. When in chemistry it was discovered that the 
elements always combined in definite proportions, the 
science of chemistry was born anew; and Professor 


112 


FIRST BUSINESS USES 


Tyndall declared that Faraday’s discovery of these 
laws of definite electro-chemical decomposition was of 
equal importance. And we shall soon see how the 
discovery was followed by an improvement in voltaic- 
batteries—to speak only of one immediate result. 
Electro-plating, too, was at once put upon a scientific 
basis, together with the art of electrotyping—and the 
importance of these applications has been growing 
ever since. 


CHAPTER XI 


THE TELEGRAPH IX EARLY FORMS 

The year 1835 saw, besides Davenport’s locomo¬ 
tive, the establishment by Morse of the first experimen¬ 
tal telegraph line. In that year the University of Xew 
York made Morse a professor, and he built a rude 
model of the telegraph in his apartments in the Uni¬ 
versity Building. But, owing to the weakening of the 
current by the resistance of a long circuit, the work¬ 
ing of the model was not satisfactory for any length 
of time. The batteries soon became weaker, also, by 
reason of the electrolytic action upon the copper plate 
which, decomposing the acid of the battery, sent ions 
of hydrogen to the positive copper, and these cling¬ 
ing to its surface prevented to some extent the action 
of the acid, and acted on the acid solution itself. These 
difficulties were both somewhat remedied by inven¬ 
tions of the year 1836, one made by Morse himself, 



LLL—Levers. EEE—Electro-Magnets. MMM—Mercury Cups. 

and other by Professor Daniell of London. Morse’s 
invention was the telegraphic relay—a means for 
strengthening the weakened current in the course of 
the circuit. Daniell’s invention was a better battery, 
one that removed the trouble caused by electrolysis. 

113 









114 THE TELEGRAPH IK EARLY FORMS 


The relay was thought out to answer the objection 
that his line would soon reach its limit of distance. 
Morse answered, “ If I can succeed in working a mag¬ 
net ten miles [away] I can go around the globe.” 
But he knew an additional device was necessary to 
strengthen the original current, and between 1835 and 

1837 he worked out the “ relay.” Ho reasoned that 

%/ 

even much weakened, the current might have power 
enough to close another circuit. lie therefore put a 
second battery at the end of the first circuit, and used 
the power of the first circuit to turn a little lever that 
dipped a bent wire into two cups of mercury, thus 
closing the circuit of the second battery. This could 
then send power on close a third circuit and so on. 

The principle may be compared to a set of reser¬ 
voirs at a distance from one another, and so arranged 
that the flow from the first will fill a long pipe at the 
end of which it raises a float that turns on a second 
reservoir, and so on. 

Of course the batteries could be opened or closed by 
sending impulses along the first circuit, if a spring is so 
arranged as to open each following circuit when the 
impulse is stopped. 

Such was the means of supplying new current to a 
long line. As to the Daniell battery, this was a 
means of remedying not only the gradual weakening 
of the voltaic battery, but also of correcting its tend¬ 
ency to weaken, thus keeping the current at a nearly 
constant state. 

Daniell was the son of an English lawyer, and after 
a classical education was so strongly attracted to 
natural science that he entered a simar refinery, and 
made improvements in its processes. At the age of 


THE TELEGRAPH IK EARLY FORMS 115 


twenty-six, he started a scientific journal that was con¬ 
ducted successfully lor many years. He made many 
studies in meteorology—the science of the weather— 
and published able articles on the subject, and when he 
was forty-one became Professor of Chemistry in the 
new King’s College, London. 

Ilis battery was based upon the principle of sur¬ 
rounding the copper element with a solution of blue- 

stone or copper-sulphate. This, 
upon the coming of the hydrogen, 
decomposes, and the resulting 
chemical combinations with the 
hydrogen make two new sub¬ 
stances. One is metallic copper, 
and this is deposited on the copper 
element, renewing its surface. 
The other is sulphuric acid which 
strengthens the acid solution in 

_ the battery. 

The Daniell Battery mi • . 

Ckll this was a most ingenious 

method of converting a weakness 
into a source of strength; and the practical method 
of making up the cell was quite as remarkable. 
The cell was a glass jar, containing dilute sulphuric 
acid. A sheet of zinc was coiled into an almost closed 
cylinder, which stood in the sulphuric acid solution. 
Inside the zinc cylinder was a porous earthenware 
cup, filled with copper-sulphate solution ; and standing 
in this was a similar nearly closed cylinder of copper. 
Then a porous basket of copper was put into the cylin¬ 
der of copper, dipping into the copper-sulphate solu¬ 
tion inside, and containing crystals of copper-sulphate. 

Suppose a circuit to connect the copper and zinc 























116 THE TELEGEAPH IN EARLY FORMS 


cylinders. The current then passes through the solu¬ 
tions, the zinc being acted on to form sulphate of zinc 
and to liberate hydrogen. The hydrogen passes 
through the porous jar, meets the copper sulphate, and 
combines with the sulphur, freeing the copper. The 
copper is deposited on the copper-plate, while the 
sulphur and hydrogen combine into sulphuric acid, 
strengthening the solution. As the copper-sulphate 
gives up its copper it is renewed by the copper-sulphate 
crystals in the basket. If there is a steady supply of 
the copper-sulphate and the zinc, the battery will keep 
up practically a constant current, for the copper sur¬ 
face is continually renewed. In brief form it may be 
said that the Daniell battery changes its waste prod¬ 
ucts into the useful forms of copper and sulphuric 
acid. 

As it is the current that determines what we may 
call the “ circulation ” of the chemicals in the battery, a 
Daniell cell should be kept in use to prevent a general 
mixing. But with slight attention the Daniell battery 
proved most effective, and particularly valuable to the 
infant science of telegraphy; and though we shall see 
that it had practical objections, these were relieved 
to some extent by improvements upon the original 
form at a later date. 

The effect of the invention of a constant current 
cell was at once seen in a rush of improvements in 
telegraphy. Besides Morse, Steinheil of Munich, and 
Wheatstone and Cooke, in England, were early in the 
field with practical systems for sending intelligence. 
In 1837, Morse was able so far to complete and perfect 
details that he showed his apparatus to the professor 
of chemistry' in the university, Leonard D. Gale, who 


THE TELEGRAPH IK EARLY FORMS 117 


so fully appreciated its worth that he eagerly lent his 
valuable assistance ; and on September 2 an exhibition 
of the apparatus was made before a number of specta¬ 
tors. Among these were an Oxford professor, and a 
young graduate of the University of Kew York, named 
Alfred Vail! 

A 1,700-foot circuit of copper wire along the walls 



Morse’s First Model—Pendulum Instrument 

i. Receiver. 2. Sender. 3. Type. 4. Message. 


of a big room was the line, and Morse was able to 
make and record alphabet-signals instantaneously by 
means of his apparatus. This, though a crude enough 
contrivance compared to its followers, contained the 
same right principles that are still in use throughout the 
































































































118 THE TELEGRAPH IN EARLY FORMS 


United States, and most of the telegraph lines of the 
world. There were a sending and a receiving device, 
both connected in one circuit to which one voltaic 
battery supplied a current. The receiver was a square 
upright wooden frame, on which hung an A-shaped 
pendulum, to the lower end of which was attached a 
weighted pencil. Beneath this, touching the pencil, 
ran a paper-ribbon moved by clockwork. So long as 
the pendulum was still, the moving of the paper-ribbon 
caused a straight line to be drawn upon it. In front 
of the pendulum was an electro-magnet around whose 
coils the current passed. When the current passed, 
the magnet pulled the pendulum aside, and caused the 
pencil to make a V-mark in the line. Shutting off the 
current let a weight bring the pendulum to its first 
position. Thus every time the current was turned on 
a V was made in the line, at longer or shorter inter¬ 
vals. Such was the recording instrument. 

Also in the same circuit was the sending instru¬ 
ment. This was a seesaw lever at one end of which 
a forked wire was held so that the ends completed a 
circuit when dipped into two cups of mercury, each 
of which was in connection with an end of the circuit. 
On pressing down the lever the wire connected the 
two cups, making a circuit. 

The other end of the lever was weighted so as to 
break the circuit when the lever was released. On 
the under side of the same end was a point so fixed as 
to be raised and lowered bv a band bearing projections 
on the upper surface. Morse had made lead types 
having such projections; and by setting these types in 
a groove, and by pushing them under the lever it was 
raised and lowered, making and breaking the circuit 


THE TELEGKAPH IN EAELY FOKMS 119 


according to the projections on the types. A type of 
one projection would make a V-mark on the recorder 
ribbon, one of two projections would make a Y Y-mark. 

Thus the recorder could at will be made to mark a 
line, points, or spaces; and by a combination of these, 
Morse had designed numerals should be telegraphed. 

A reason for the great value of this invention is the 
few elements that made it up, the simplicity of its ac¬ 
tion, and the permanent form of the record. It was 
telegraphy reduced to the lowest terms, and conse¬ 
quently could hardly be improved upon in principle. 

The young graduate, Alfred Yail, was so strongly 
impressed with the great value of the invention, and 
with its possibilities, that he soon interested his father 
—a prominent iron-worker, who had made the shaft 
for the Savannah , the first transatlantic steam vessel. 
The elder Yail Avas told by Morse that the United 
States Government had issued through the Secretary 
of the Treasury a circular of inquiry on the question 
of establishing a system of telegraphy in the country, 
and he agreed to furnish the capital for making mod¬ 
els, securing patents and showing the invention to 
Congress. Judge Yail, the father, had already been 
interested in the first American railways, and though 
it was a time of panic, he agreed to lend the necessary 
$2,000 on behalf of his son in return for an interest in 
the enterprise. Alfred Yail Avas to make and sIioav 
the Morse apparatus, and to receive a one-quarter in¬ 
terest. 

While Yail and an assistant constructed an appa¬ 
ratus in New Jersey, Morse prepared a description of 
his invention and filed a caveat at Washington to pro¬ 
tect his invention. In this document it appears that 


120 THE TELEGRAPH IN EARLY FORMS 


he had in mind the sending of numbers that were to 
be read by means of a dictionary of words represented 
by numbers. This plan seems to have been improved 
by Vail, who made the recorder lift and drop the pen¬ 
cil instead of pulling it aside, and who substituted dots 
and dashes for the V’s, and indicated letters of the 
alphabet instead of numbers meaning words. 

Also in this busy year occurred the improvements 
made by Steinheil in the original telegraph of Gauss 
and Weber. They had used, for a sender, in their line 
of one and a quarter miles, Faraday’s principle of induc¬ 
ing a current by putting a magnet into a coil of wire ; 
but they raised and lowered a coil that rested around 
a big bar magnet set upright. Their receiving appa¬ 
ratus was a heavy magnetic bar hung b} 7 a cord, and 
swinging horizontally in a square-coiled wire connected 
to the circuit. The needle or bar swung right or left 
when the sending-coil was raised or lowered. This 
movement turned a little mirror placed on the cord 
and reflected a spot of light to and fro along a scale. 
The mirror was placed so as to reflect the scale, and 
by looking through a little spy-glass, the signals could 
be read. It certainty was a heavy, clumsy, mechan¬ 
ical contrivance. 

Steinheil to whom Gauss and Weber—who were 
more effective in theory than in practice—had referred 
their telegraph, was able to improve it in every fea¬ 
ture. He made a stronger rotary sender, and for a 
recorder invented a clever arrangement by which the 
turning of two pivoted magnetic needles made ink dots 
upon a paper ribbon. Th q principle of the receiver, 
as will be seen, was not very different from Morse’s 
instrument, though less simple. Rut Steinheil, in try- 


THE TEI.EGKARH 11S3 EARLY FORMS I*J! 


ing to make use of the rails of a. railway as pari of a, 
circuit, made a most valuable and helpful discovery 
—namely that instead of a ret urn circuit, the earth 
might be used. Thereafter, instead of a double line, a 
single line with extremities buried in the earth was 
commonly used in telegraphy. This earth connection 
was not whollv new, since it had been used in all the 
telegraph lines that employed frictional electricity ; 
but to realize that the earth might be used in oomplet- 



Hteinheil’h Improved Receiver 


The capillary tubes CC carry ink from the 
reservoirs RR when actuated by the magnets, 
and strike the paper strip, which is unrolled 
by clockwork from the spool I). 

ing a battery-circuit was another matter, and greatly 
simplified telegraph construction. 

Suppose a telegraph line to lx; likened to a closed tube 
full of water flowing from Bender to receiver and then 
back again ; then suppose it to be found that the earth 
was full of water that could be admitted at one end of 
the tube and left to flow back into earth again, and 
you will have a good ideal of the action o! an earth cir¬ 
cuit. Whatever is the cause of the diaturbanoo known 

















122 THE TELEGRAPH IN EARLY FORMS 


as an electric current, it loses itself when brought into 
contact with the great earth as a river is lost in the 
ocean, thus leaving the remaining part of the circuit 
free to receive impulses from without. 

In this year also was patented the telegraph appa¬ 
ratus of Wheatstone and Cooke—one based on the 
principle of deflecting a needle. Discovered by Oer¬ 
sted, this principle had 
been applied already by 
Gauss and Weber, im¬ 
proved by Steinheil, and 
by Schilling in St. Peters¬ 
burg. Schilling’s appa¬ 
ratus was a small key¬ 
board like that of a piano. 
Each key when pressed 
could deflect a needle at 
a distance—right or left, 
as a positive or negative 
current was sent. Five 
needles thus gave ten 
signs, and these were 

The needles are actuated by coils placed combined into a Code, 
behind each one, and operated from the key¬ 
board. The letters and numerals are indi- Williaill Cooke WaS 
cated on the dial by the convergence of two 

needles - shown this apparatus at 

Heidelberg, and returning to England was introduced 
by Faraday to Wheatstone, and the two together 
worked out an application of the deflected needles in 
1837. It must not be forgotten that a number of 
other inventors were working on similar lines, and 
that only those who made practical instruments are 
here mentioned. Wheatstone was professor of exper¬ 
imental philosophy in King’s College, London (Dan- 



Cooke and Wheatstone’s In¬ 
strument 








THE TELEGRAPH IK EARLY FORMS 123 


iell was in the same faculty), and spent his life in inven¬ 
tion and research. Cooke was the more businesslike, 
and they worked well together. 

Their first apparatus consisted of five needles 
pivoted on a vertical board that was diamond shaped. 
By means of a keyboard any of the needles could be 
deflected right or left, and when so deflected the letter 
indicated was found where the needle or needles 
pointed. If two of the needles pointed, the letter in¬ 
dicated was at their intersection—that is, where they 
would meet if sufficiently lengthened. This was the 
sort of apparatus described in their first patent, but 
it was later improved though with little change of 
principle. It was altogether far more complicated 
than Morse’s telegraph, and so much more likely to be 
out of order at times. But even these did not ex¬ 
haust the list of inventions of 1837 ; for in this year 
Yail, Morse’s partner, suggested a printing telegraph 
—an idea that was afterward perfected in more than 
one form; there were several new motors; and a 
most delicate galvanometer, capable of measuring ex¬ 
actly the relative strength of two currents was made 
by Pouillet—one that is still in use. Savary discovered 
that the discharge of a Leyden jar was an oscillation, 
instead of a single impulse in one direction ; a fact 
subsequently discovered and developed by the Ameri¬ 
can, Professor Henry. 

In fact, at this busy time the applications of the 
science were so many and so various that it becomes 
impossible to give attention to more than those in¬ 
volving some new or striking idea. Even the question 
of who invented a particular improvement becomes a 
difficult matter of the weighing of evidence and the 


124 THE TELEGRAPH IX EARLY FORMS 


comparison of dates even clown to weeks and days ; 
and after we have done our best the credit may be 
unfairly awarded. In a recent discussion (1906) the 
question of the credit due inventors was the topic 
among certain eminent engineers, and the result, as 
stated by one of them, seems to be that the term “ in¬ 
venting ” should be confined to the introduction of 
new principles rather than adapting known principles 
to “ new situations and conditions.” But—what is a 
“ new principle ” ? Is it more than a very important 
and widely applicable idea ? The best definition 
seems to mean only this; for it reads (Century Diction¬ 
ary) “ A truth which is evident and general; a truth 
comprehending many subordinate truths,” and “in 
mathematical physics, a very widely useful theorem.” 
But until the applications are made, how shall we 
know whether a theorem is widely useful ? 

In telling the story of electricity we can regard as 
new principles such only as have proved widely useful 
—as Oersted’s noting of the deflected needle, and 
Schweigger’s multiplying of coils around the needle ; 
and we shall try to give chief importance to the ap¬ 
plications that were forerunners of the devices we see 
in wide use to-day, but shall not forget that later de¬ 
velopment may make others as important. 


CHAPTER XII 


ELECTRICITY AT WORK 

A most striking and valuable application of elec¬ 
trolysis was made in 1838. Before that date it was 
known that metals could be deposited on other metals 
or prepared surfaces by sending an electric current 
through chemical solutions. This as we said earlier 
was done by Bruguatelli, of Pavia ; and De la Rive a 
Frenchman used the process for gilding wire in 1828 ; 
Bessemer plated lead castings with copper in 1834, 
and two years later De la Rue spoke of finding on the 
metallic coating of copper deposited in a Daniell’s cell, 
“ every scratch of the copper on which it is deposited.” 
All these are cited by Professor Houston ; but he says 
that no particular use had been made of these proc¬ 
esses till, in 1838, Professor Jacobi (the same who 
made the boat motor) saw their possibilities as a 
means of making metal facsimiles of the surfaces on 
which the metallic coatings were deposited. In the 
following year an English experimenter named Spen¬ 
cer read a paper based on experiments during 1837 
and 1838, in which he fully described the different 
principles of electro plating and electrotyping. An¬ 
other independent inventor of the process was a 
printer named Jordan. Thus Jacobi, and Spencer, 
and Jordan appear to be claimants of the new art of 
electrotyping. The Britannica gives greatest credit to 
Spencer, and we shall briefly speak of his work. 

125 


126 


ELECTRICITY AT WORK 


Spencer said that he had used a copper coin in a 
Daniell battery, and found that the copper deposited 
on it came off showing a reversed copy of the coin— 
the projecting parts having left their shapes in the 
shell deposited. At another time, a little varnish be¬ 
ing spilt on the copper element of a DanielPs cell pre¬ 
vented the deposit of copper where it adhered. Thus 
Spencer had found a means of depositing copper 
where he pleased and preventing its deposit where he 
chose. He applied these principles to a sort of en¬ 
graving in relief. A copper plate was covered with a 
wax coating, and a design drawn, removing the wax 
along certain lines. Then the copper plate was etched 
—that is, put in an acid bath that acted on the ex¬ 
posed lines, eating into the copper. Next the copper 
plate was put into the voltaic cell, and copper was de¬ 
posited along the roughened lines only—the wax pre¬ 
venting action elsewhere. The plate was taken out, 
the wax melted off, and the lines stood out in relief. 

To make a plate directly from an engraved plate, he 
had only to deposit a copper shell upon it, and the 
shell, when stripped off, showed the engraved lines of 
the original plate, but in relief. He made other ap¬ 
plications of the process, and an especially valuable 
one by making moulds of clay or plaster, on w T hich by 
covering the surface with bronze powder or gold leaf 
he could deposit metal, forming a mold. 

These methods, modified, form the foundation of 
modern electroplating, electrotyping, and electro¬ 
casting. 

In 1838, Morse secured for his telegraph-system a 
French patent, having already applied for the Ameri¬ 
can patent, and having petitioned Congress for an ap- 


ELECTRICITY AT WORK 


127 


propriation to build a line long enough to prove the 
practicality of his apparatus. But his foreign voyage 
was a failure. The British refused his application on 
the ground that his invention had already been pub¬ 
lished ; and Russia also refused him any help. The 
French government, though allowing his patent, is said 
to have appropriated his invention without compensa¬ 
tion, and he returned to New York after about a 
year’s absence — there to await the meeting of the next 
Congress in the United States. Altogether, he had so 
far pursued his purpose in spite of poverty, neglect, 
and lack of powerful friends. 

In 1839 an experiment had been made in electric 
propulsion by a Scotchman named Robert Davidson. 
He made a motor that drove a locomotive at four 
miles an hour over a rough plank road, using a 40-cell 
battery; but like all attempts to make use of the 
voltaic cell for the purpose, it was an economic im¬ 
possibility to compete with other cheaper forms of 
power. Another event of this year that helped to 
bring electricity more prominently before the public 
was the blowing up of the wreck of the Royal 
George — the vessel celebrated for having turned tur¬ 
tle, going down in harbor with Admiral Kempenfeld 
and a thousand men aboard, of whom about 800 were 
lost. 

This happened at Spithead, in 1782 ; and for over a 
half century the wreck had been an obstruction. 
Upon her sinking Cowper wrote his well known poem, 
“ Toll for the brave, the brave that are no more ! ” 

In hope of saving the vessel many attempts to raise 
it were made, but in 1839 it was decided to blow her 
to pieces. Cases of gunpowder were lowered into the 


128 


ELECTRICITY AT WORK 


vessel and then exploded by means of an electric fuse. 
This fuse in its earliest form consisted of two insulated 
copper wires twisted together. Their ends were con¬ 
nected by platinum wire of very small diameter. The 
current meeting with great resistance in passing from 
the broad copper to the narrow platinum conductor 
heated the platinum sufficiently to ignite the powder. 
This elementary form has since been greatly modified, 
and instead of using a voltaic cell current, in such an 
igniter, a high-tension induction machine, operated by 
a crank or plunger has been found preferable for pro¬ 
ducing the explosion of blasting charges or for igniting 
gases and similar purposes where quick and great heat 
is needed. 

The year 1840 saw the invention of a new form of 
voltaic cell known as the Grove, from the inventor, 

William Robert Grove, a graduate 
of Oxford and a lawyer, born in 
1811. He studied electricity and 
became Professor of experimental 
philosophy at the London Insti¬ 
tution. He is known chiefly for 
his learned book on the “ Corre¬ 
lation of Forces,” and also be¬ 
came distinguished in his profes¬ 
sion, being knighted about 1872. 
Grove’s batter} 7 was an attempt 
to improve on the Daniell cell, 
and substituted platinum and zinc 
for the zinc and copper. The platinum was dipped in 
nitric acid, surrounded by a porous cup, while the sul¬ 
phuric acid and zinc plate were outside. Hydrogen 
liberated by the zinc was oxidized in passing through 



The Grove and Bun¬ 
sen Cell 




















ELECTRICITY AT WORK 


129 


the nitric acid, the resulting combinations being part 
water and part nitric peroxide gas. This gas was 
dissolved in the nitric acid, and so there was no 
“ polarization ” or deposit on the platinum. The 
Grove cell furnished a powerful continuous current. 

Within about two years, however, this battery was 
modified, at Grove’s suggestion, into the Bunsen bat¬ 
tery. 

But to Sir William Grove belongs the credit for a 
most important pioneer step taken in the same year, 
no less than the first incandescent electric lamp. It 
was described in the Philosophical Magazine in 
1845, and consisted of a bit of partly coiled platinum 
wire attached at each end to the bared ends of copper 



Grove’s Incandescent Lamp, 1846 


wires from several of his own voltaic cells. Upon the 
passing of the current the platinum wire was heated to 
incandescence, and gave a light by which he could read 
or carry on experiments for several hours. 


















































130 


ELECTEICITY AT WOEK 


Of course this was merely a “ laboratory ” device, 
being expensive, of short continuance, and entirely de¬ 
pendent upon the voltaic battery current, which was 
still far from perfected. The platinum wire as he used 
it was covered by an upturned glass, resting in another 
glass vessel — so as to exclude the air, and thus to pre¬ 
vent the rapid consuming of the platinum, and in his 
account of the light he noted the possibility of putting 
the platinum coil into a closed glass globe. 

It was in 1810 that Morse succeeded in obtaining his 
United States patent. It was issued June 20, and num¬ 
bered 1,617 — a number that is instructive in view of 
the high numbers we see attached to patents of our 
own day ! — there being 650,000 granted even so long 
ago as January 1, 1900. But Morse’s real triumph did 
not come until four years later, after the experimental 
outdoor line was put into working order, and mean¬ 
while he was put to great straits to make a living. 
In 1810, also, Cooper of England, suggested the use of 
carbon to replace copper in voltaic cells. 

The following year saw the first electrotype plate 
made for printing and used by an American, J. Adams, 
and also another platinum incandescent light made by 
Frederick de Moleyns of England, but no immediate 
practical use followed for the same reasons that pre¬ 
vented the use of the device of Sir William Grove — the 
expense, the irregularity of current, and the liability 
of the platinum to melt if for any reason the current 
raised it to a higher temperature than would give the 
white heat desired. Professor Wheatstone in this year 
took out a patent for a device that was greatly im¬ 
proved at a much later time. This was a printing tel¬ 
egraph— one that was to print its message in the reg- 


ELECTRICITY AT WORK 


131 


ular alphabet. This was to be done by using the cur¬ 
rent to bring about contact between a strip of paper 
and a wheel on the edge of which were the type let¬ 
ters. The wheel revolved so as to bring the right let¬ 
ter over the paper, and then a current was sent 
through the line to press the two into printing con¬ 
tact — as in a modern “ stock-ticker.” But this mechan¬ 
ism did not come into use. The year 1842 was espe¬ 
cially notable for the researches into new fields of 
theory. Professor Henry—who as an original worker 
was hardly less successful in practical discoveries than 
Faraday himself, succeeded in studying out and clearly 
explaining a problem that had proved something of a 
puzzle. This was the occurrence of what was known 
as ‘‘anomalous magnetism.” When a steel bar is 
placed inside a coil through which a Leyden jar is dis¬ 
charged, it becomes magnetized, but in a most remark¬ 
able fashion if the discharge is sudden, as the bar 
is found to contain alternate layers of opposite 
magnetism. This may have been discovered by filing 
magnetized bars into shape, and was shown by Henry 
to be due to the fact that the discharge of a Ley¬ 
den jar is really a rapid interchange of opposite cur¬ 
rents— a vibrating back and forth of currents, each of 
which acts upon the steel bar. But the science of mag¬ 
netism may fairly be considered a separate branch of 
electric theory, and is a study in itself not to be in¬ 
cluded in so general a survey as we must permit our¬ 
selves. 

Henry also in the same year discovered the oscilla¬ 
tory — or to and fro — nature of the electric discharge. 
This had been shown in 1837 by Savary, but Henry 
went further, proving that waves in the ether were 


132 


ELECTRICITY AT WORK 


set up at the same time — a very early hint of the most 
modern theories of electricity. Henry also con¬ 
structed induction coils — an application of Faraday’s 
experiment on induced currents but probably based 
on his own discoveries, and original with Henry though 
Page of Washington had made them in 1838. 

In fact, to appreciate fully the place of so great a 
man as Henry in electric science it is necessary to 
study deeply into the science and the theory of the 
whole subject. He was “ by general consent the fore¬ 
most of American physicists,” and the list of his 
achievements covers an enormous range of scientific 
subjects. 

The induction coils must be explained as they play 
a large part in the present day applications of elec¬ 
tricity to daily needs. Starting with Faraday, Page, 
and Henry, there were numerous forms of apparatus 
made with one general purpose, namely to change the 
nature of currents, in amount or in intensity. Once 
more resorting to the comparison with water, we may 
say that it is as if we used a reservoir of water to send 
a supply to another point, and there either to furnish a 
large amount at a slow rate of flow, or a smaller 
amount at a swifter rate of flow. By means of induc¬ 
tion coils, a current of electricity can be changed in 
intensity. The method’ of doing this is as follows : 
The current is made to flow through a coil of wire, 
and this coil is used to induce a current in a second 
coil of wire. If the first coil has wire of few turns 
and large diameter the current meets slight resistance. 
If the second coil has many turns and wire of small 
diameter, the resistance is great. Now remembering 
the rule that current is proportional to the electro- 


ELECTRICITY AT WORK 


133 


motive force divided by resistance (c=~) 1 or 

amperes= re Jatan Ce we shall see that as the resistance 
is greater, the current decreases in volume but in¬ 
creases in intensity. Thus the new current becomes 
one of small volume and high pressure. 

This condition, of course, is reversible. If the sec¬ 
ondary coil has the larger wire and fewer turns the 
induced current is decreased in pressure or electro¬ 
motive force and increased in volume. It is as if we 
made a river flow through a channel of varying width ; 
where the channel is narrow the rate of flow is quick, 
where it is broad, the rate of flow or current is slow 
— though the same amount of water passes a given 
point in either channel in the same time. 

The induction coils are sometimes known as “ trans¬ 
formers ” and called “ step-up ” or “ step-down ” trans¬ 
formers according to whether they increase intensity 
or diminish it. 

The actual instrument especially designed for this 
purpose was invented in 1812 by Masson and Breguet, 
though afterward (in 1851) greatly improved by an in¬ 
strument-maker after whom it has been named the 
Buhmkorff Coil. A primary coil of wire, of large 
diameter and moderate length is inserted in the mid¬ 
dle of a secondary coil formed of wire of fine diameter 
and many turns. Each coil is of insulated wire, and 
the two coils are insulated from each other. Inside 
the primary coil is a soft iron core, a bundle of thin 
wires being used. This core helps the action of the 
apparatus, and is also used to interrupt the currents, 
as will be seen. 

1 This is now usually written I=§, I being the symbol for current 
intensity in amperes. 


134 


ELECTRICITY AT WORK 


It will be remembered that induced currents are 
formed only while the primary current is increasing 
or decreasing, or while it is being made or broken. 
So there is a little lever or spring key so arranged 
that it is moved whenever the soft iron core is mag¬ 
netized by the primary current, and, being moved, 
breaks the connection of the primary current. This 



Diagram of the Ruhmkorff Induction Coil 

C—Core. P—Primary coil. S—Secondary coil. The device 
at the right B is employed for rapidly and automatically break¬ 
ing and making the circuit of the primary coil. 

current breaker produces a continual making and 
breaking of the primary current thus : A current is 
sent from a battery through the primarj f coil. It in¬ 
duces a contrary current through the secondary coil. 
The core is magnetized. The core moves the lever, 
shutting off the primary current. This induces a sec¬ 
ond current (opposite to the first induced current) in 



















































































ELECTRICITY AT WORK 


135 


the secondary coil. The magnet acts again, and so 
on, the interrupter being so rapidly vibrated as to give 
out a musical note. 

Attached to the instrument also is a commutator, 
by means of which the direction of the primary cur¬ 
rent can be changed from positive to negative, or shut 
off at will. 

There are also other means of changing the electro¬ 
motive force of the induced currents, but these may be 
left undescribed here. But it should be explained 
that the inductive action in the primary coil itself pro¬ 
duces extra currents opposite to those coming from 
the battery whenever contact is made. These oppose 
the establishing of the current sent, and strengthen 
the reverse current set up when the current is broken. 
This makes the current at the breaking stronger than 
at the contact, and this current sends a strong spark 
between the ends or terminals of the secondary coil — 
usually two brass knobs separated more or less. 

The current given from the secondary coil can be 
increased or diminished by having the primary movable 
within it — thus allowing it to be more or less influ¬ 
enced. The same effect is at times produced by in¬ 
closing the inner coil in a copper tube or shield , that 
can be more or less interposed. When in the way it 
interrupts the induction, by what Atkinson (in “ Elec¬ 
tricity for Everybody”) calls “ an electric eddy cur¬ 
rent,” which is of course derived from the primary 
and lessens it by acting against it. 

In 1842 also Morse made some experiments in New 
York harbor in order to test the possibility of using a 
current through the water. One moonlight night he 
went in a rowboat from the Battery to Governor’s 


136 


ELECTRICITY AT WORK 


Island, unrolling an insulated wire as he went, and 
succeeded in sending signals between these two points, 
thus convincing himself that “submarine telegraphy ” 
was at least possible. But unluckily a passing vessel 
hooked up the wire on her anchor, and broke it off. 

At this same period there was a great deal of most 
valuable work done by the workers upon the theories 
underlying the electric action. For it will be remem¬ 
bered that workers now had in their hands a number 
of instruments by which they could tell the force, the 
volume, the direction, and the presence or absence of 
the electric charge and currents. Among these work¬ 
ers mav be named William Thomson — afterward Lord 
•/ 

Kelvin, Helmholtz, and especially J. Clerk Maxwell. 

William Thomson, born in 1824, distinguished him¬ 
self as an original thinker even while still a student, 
and in 1846 became Professor of Natural Philosophy in 
the University of Glasgow. Even before this, in 1842, 
he had published valuable researches upon electricity. 
We shall see him credited with most useful discoveries 
and inventions all through the development of the 
science, and he is still actively interested. Hermann 
Helmholtz, three years his senior, was Professor of 
Physics in Berlin, and died in 1894, equally distin¬ 
guished for his work in physiology, mathematics and 
physics. Maxwell, a Scotchman born in 1831, was 
writing scientific papers at the age of fourteen, was 
distinguished, at Cambridge, and in 1871 was Professor 
of Experimental Physics at that University, dying in 
1879. 

Of all the investigators into the nature of elec- 
. tricity and its laws, he is easily first, his work be¬ 
ing the “ classic ” on the subject. This was published 


ELECTRICITY AT WORK 


137 


under the name “Electricity and Magnetism ” in 1873. 
Of course lie was still a boy at the time we are now 
considering, but is mentioned here merely to group 
the names of some of the more prominent theorists as 
a reminder of the work that was being done in labora¬ 
tories for the aid of the more practical, workshop 
achievements. 

It is hardly possible that any man should accom¬ 
plish equal results in both theory and practice, and it 
is most unfair that the maker of the machines should 
become famous, while the thinker who has made the 
machine a possibility remains unknown except to 
scholars. When in reading books on Electricity we 
see references to “ laws,” or “ principles,” or “ theo¬ 
rems,” we must not forget that to construct these is 
often much more difficult and even more practically 
useful than to apply them to a single apparatus. 

For example one of the most useful investigations to 
electric science was carried on from 1840 to 1889 by 
the English physicist, James Prescott Joule, who was 
a fellow worker with Thomson. In 1843 lie proved 
that the mechanical and the heating power of the elec¬ 
tric current were proportional; and in the same year 
showed that the quantity of heat needed to increase 
the temperature of a pound of water by one degree 
Fahrenheit is equivalent to the energy that will lift 
772 pounds a foot. This law announced in 1843 be¬ 
came known as “ Joule’s Law,” and enabled experi¬ 
menters to measure electricity in mechanical terms, 
for he had shown in 1840, that the heat caused by a 
voltaic current in a metal conductor may be calculated 
bv multiplying the resistance into the electric current, 
squared , and this into the time in seconds the current 


138 


ELECTRICITY AT WORK 


lasts. To put it in a formula, Heat = Current 
(squared) X Resistance X Time, or H = C 2 Rt. This 
formula gives the number of units of heat, and as the 
unit of heat has been fixed at the amount necessary to 
raise 1 gramme of water to 1° Centigrade, we simply 
multiply the number of units of heat by this value, 
and have an exact value for the results of the formula. 


CHAPTER XIII 

MAKING THE SCIENCE PRACTICAL 

During the early days of 1843, Professor Morse 
was still straggling along in the hope of securing aid 
from Congress for which he had applied in the 
previous December. In March there was no action un¬ 
til the very last day of the session, when the bill was 
passed appropriating $30,000 for the work of an ex¬ 
perimental line. Morse declared “ this was the turn¬ 
ing point in the history of the telegraph. My per¬ 
sonal funds were reduced to the fraction of a dollar, 
and had the passage of the bill failed there would have 
been little prospect of another attempt on my part to 
introduce to the world my new invention.” 

Morse and Vail at once went eagerly to work build¬ 
ing the line from Baltimore to Washington, and also 
making the hundred and one experiments needed to 
adapt the idea to actual use. In these, Vail’s work 
was most important, and has not been sufficiently rec¬ 
ognized, possibly in fear of diminishing the credit due 
to Morse. Vail invented a circuit breaker (like that on 
the Ruhmkorff coil) and an instrument for measuring 
current-strength, besides many minor improvements. 

The laying of the line was attended by great diffi¬ 
culties, the wires being put under ground. After ten 
miles were buried — the line suddenly failed to work. 
The inventors and contractors were in despair, holding 
daily consultations. Out of $30,000, all but $7,000 
was spent, and of this the contractor of the line 
claimed $4,000. This man was a member of Congress 

139 


140 MAKING THE SCIENCE PRACTICAL 


named Smith who had entered the partnership. Dis- 
union and trouble set in and the year ended in com¬ 
plete discouragement. It seemed as if all the appro¬ 
priation was to be spent without even completing the 
line, and Mr. Smith was threatening to oppose the 
granting of a new appropriation. 

Abroad, the year was marked by an invention made 
by Professor Wheatstone and Professor Jacobi, inde¬ 
pendently — a means of readity varying at will the re¬ 
sistance of any electric circuit by introducing an appa¬ 
ratus known as a rheostat. This in its early form was 



Diagram of the Rheostat 

Each of the square stops is connected with a resistance coil 
underneath and the coils connected in series. On the left is a 
nputral coil. The switch being moved to the right, it cuts out 
the coils successively till it reaches the right, when the cur¬ 
rent passes direct. 

made by coiling wire on two cylinders of the same 
size, one of wood, the other of brass, and so arranged 
that the current is resisted more and more as the 
length of wire wound on the wooden cylinder was in¬ 
creased. A longer description is not necessary, since 
much better instruments have since been devised. 







MAKING THE SCIENCE PRACTICAL 141 


Likewise in 1845, there was another use of the elec¬ 
tric current in blasting, when a great cliff was des¬ 
troyed, by means of the electric fuse. This was at 
Dover, and three charges were used, 18,500 pounds of 
powder being fired at the same moment by voltaic bat¬ 
tery. The advantage of this simultaneous blasting 
over successive explosions was very great, and is evi¬ 
dent. The electric current made it possible and easy, 
whereas by any other method it would have been 
most difficult. Professor Wheatstone in England laid 

a wire across the bed of the River Thames, eight 

% 

months after Morse’s similar experiment in New York 
harbor, and succeeded in sending current through; 

It is interesting to learn that during the period of 
depression about the Morse telegraph line, Alfred 
Yail devoted himself to reading Faraday’s Researches 
in the hope of finding a way out of the troubles. By 
February the decision was made to put the wire on 
poles instead of underground — a tiling that had been 
done virtually by Weber at Gottingen in 1823, as was 
mentioned—and during March and April this work 
went on . By April 12, twelve miles were successfully 
wired, Yail signalling to Morse at Washington along 
the line as built. Later in ApriL, an earth circuit was 
used for part of the line, applying Steinheil’s discovery. 
On May 23, 1844 the line was done as far as the Bal¬ 
timore depot at Mount Clare. 

The year before, 1843, Morse had promised Miss 
Ellsworth the honor of sending the first mes¬ 
sage. 

Toward the close of the session of Congress, Morse 
had been in attendance upon the Senate. The last day 
came, and he left at nine o’clock knowing that about 


142 MAKING THE SCIENCE PRACTICAL 


a hundred other bills would come up before his own. 
That night he found he had only seventy-five cents be¬ 
yond the price of his ticket to New York. Next 
morning, as he was leaving, he was told that a visitor 
was in the parlor to see him, and when he entered the 
room he met Miss Annie Ellsworth, daughter of the 
Commissioner of Patents — one of his warmest friends 
in Washington. She offered congratulations, to 
Morse’s surprise, and then told him her father had re¬ 
mained to the end of the session, and knew that the 
bill had been passed March 3, 1843. 

“ Annie,” Professor Morse replied, “ the first mes¬ 
sage from Washington to Baltimore shall be sent from 
you ! ” She was the first to give him the good news. 

On May 24, the line was finished, Miss Ellsworth dic¬ 
tated the message, “ What hath God wrought ?” and 
Morse at 8:45 A. M. sent it successfully to the Balti¬ 
more end of the line. This was the beginning of 
commercial telegraphy by the Morse system. 

Meanwhile Yail had begun transmitting simply by 
hand, making and breaking contacts without the use 
of transmitting mechanism, and soon made a little 
spring-key for the purpose — thus making the working 
of the line simpler. And the complicated recording 
instrument also was before long to be gradually re¬ 
placed by a simple “sounder” which the operator 
reads by hearing. Still, these were but omitting 
features by experience, and the fact remains that the 
first telegraph designed upon right principles was 
built upon the plans and carried through by the ef¬ 
forts of Professor Morse. By this fact he must be 
judged, rather than by the fate of his apparatus when 
time had caused it to be improved. As for the Morse 


MAKING THE SCIENCE PRACTICAL 143 


Alphabet, it may be that it was worked into its pres¬ 
ent form by Vail, as shown by Franklin L. Pope in 
the Century Magazine for April, 1888 ; but the un¬ 
derlying idea, as a later correspondent showed in a let¬ 
ter to the same magazine may be traced at least as far 
back as Francis Bacon’s secret alphabet, and Vail’s 
work upon it was mainly that of an improver. 



By depressing the lever of the key the circuit is closed at A. 

This causes the sounder at the other end of the line to be ac¬ 
tuated by an electro-magnet, thus repeating the signal, giving 
a series of clicks, which are read by the operator. 

There is no need for weighingtoo exactly the claims 
of rival inventors, especially if, as here, they were part¬ 
ners working toward one purpose. A remark by either 
during their work might be the germ of an invention 
by the other, and such suggestions might have been 
exchanged daily without any record being made. 
Every inventor must be fed upon the ideas of others. 

Between 1841 and 1844 two French experimenters, 
Deleuil and Archereau had been showing various elec¬ 
trical displays in Paris, and are said to have shown 
the electric arc in a vessel closed against the air to 
make the carbons last longer. But though the princi¬ 
ple was right, there were commercial difficulties that 
prevented them from making the light available for 






















144 MAKING THE SCIENCE PRACTICAL 


public use, since there were no good carbons, and no 
steady and cheap current to supply large lamps. Be¬ 
sides, there was as yet no way of keeping the carbons 
just far enough apart to permit the formation of the 
arc, and when carbon had been burned so as to in¬ 
crease the distance, the circuit was broken and the 
lights went out. Further inventions were needed to 
remedy these defects. 

The next year, 1845, saw an improvement in the in¬ 
candescent light. A young American named John W. 

Starr, of Cincinnati, is declared by the 
authors of “ The Electric Light,” Al- 
glave and Boulard, to be probably the 
inventor of the incandescent carbon 
light. Incandescent wires had been 
used, but even platinum, the best for 
resisting the high temperature, had to 
be kept at temperatures lower than 
would give a clear white light, and at 
these it gave a yellow or red light. 
Something less fusible was sought, and 
while, we read in the book quoted, 
these were “ not wanting, most of them 
could not be reduced to line wires, 
and burned readily.” Carbon if kept 
toT^andescence^ythe in a vacuum was the desired substance. 
current ‘ The lamp made by De Moleyns in 

1841 had a device for dropping powdered carbon on its 
incandescent platinum wire, but the whole lamp was 
not effective. Starr’s lamp inclosed a rod of carbon 
in a vacuum, or “ vacuous space,” as Houston terms 
it, formed in a glass oblong tube. The current was 
brought in by platinum connections. 



Diagram of 
Starr’s Lamp 





















MAKING THE SCIENCE PKACTICAL 145 


Starr was too poor to do much by himself, but was 
aided by George Peabody the philanthropist. Taking 
a man named King as a partner, he sailed for England, 
and there exhibited his lamps. One exhibit was a 
candelabra of twenty-six lamps to typify the number of 
the States in the Union at that date. Among the 
spectators was Faraday, who helped in the experiment, 
admired the lamps, and predicted success. 

Soon after, Starr and King embarked for America, 
and next day Starr was found dead in his berth. He 
was only twenty-four years old. King had patented 
the lamp, describing its main features, and stated that 
more than one could be used in the same circuit, and 
that either a battery or magneto-electric machine 
would operate the lamps. 

Except that the method of securing the partial vac¬ 
uum differed, Starr’s lamp has all the main features 
of the incandescent lights of to-day though in a far in¬ 
ferior form. The current required to raise a thick 
carbon to incandescence was of course largely wasted, 
since only its surface could give light. Indeed in a 
recent article an electrical expert is quoted as declar¬ 
ing of it, “ It produced a brilliant light, but was in 
various aspects unsatisfactory.” Nothing ever was 
done by King, Starr’s partner in the enterprise, and 
his name is connected with the lamp only because the 
patent was taken out in his name. Professor Houston 
remarks that this invention “discloses a remarkable 
knowledge of the subject, considering its early date.” 

The same vear saw the issue to Wheatstone of an 
%/ 

English patent for the use of an electro magnet as a 
field magnet in place of a permanent magnet, in 
electric machines, thus giving them greatly increased 


146 MAKING THE SCIENCE PRACTICAL 


power, and enabling them to be ran by a battery ; 
and Faraday made another “ pioneer ” discovery of 
most striking value. He had been experimenting on 
polarized light, and found that its rays were caused to 
rotate by a magnet—suggesting at once a connection 
between electricity and light, and one afterward 
studied in developing the theories of electric vibration. 

We cannot here go into the matter of the polarizing 
of light beyond the general fact that it is supposed to 
be caused by a change in the direction of the ether 
waves causing light, and that the action of the mag¬ 
net was an indication that both magnetism (and there¬ 
fore electricity) and light were caused by a motion in 
the ether. There were also certain studies by Neu¬ 
mann upon the mathematical theory of induction, which 
the reader may consider only for the purpose of bear¬ 
ing in mind how each new phenomenon in the prac¬ 
tical science of electricity was at once made the basis 
for deep reasoning by scholars, and the announcement 
of the exact laws governing it. We are far too likely 
to consider discoveries and inventions as proceeding 
from a certain vague faculty we name “genius,” and 
it is well to remember Faraday magnetized thousands 
of needles under various conditions in order that he 
might be sure of some suspected principle of action. 

The value of such studies also appears in the fact 
that whenever the arts have hit upon something new, 
the men of science are able to foresee how the new 
thing may be applied ; and when the practical men 
have found a need, the men of science are able to 
point out how it is to be supplied. Thus Starr’s 
lamp contained a platinum wire fused into its glass 
bulb, making a way for the current to reach the car- 


MAKING THE SCIENCE PRACTICAL 147 


bon. As a man of science he knew that when glass 
and platinum are heated they expand at nearly the 
same rate, and so the expanding of the platinum 
does not crack the glass. This fact was probably 
known, and set down in tables of “ coefficients of ex¬ 
pansion ” long before any one had foreseen that the 
knowledge would be of use in making electric lamps. 

Classified, scientific knowledge lies ready to hand, 
like well kept tools in a systematic work-shop ; and no 
one can foresee that such bits of information will not 
be precisely what is needed to complete some widely 
useful appliance. 

Each year in electrical history is marked by ad¬ 
vance in theory and practice. In 1846, the laws of in¬ 
duction were carefully verified by Professor Weber, 
the same who worked with Gauss and with him setup 
the induction telegraph line in Gottingen ; and a new 
practical application of the heating of a platinum wire 
put into a circuit was made by Crusell of St. Peters¬ 
burg, who so arranged a loop of platinum wire that it 
could be drawn close about a vein or a small growth 
it was desired to cut off in an animal, at the same 
time that it was heated by the current. This formed 
an electric surgical cautery, that in the same operation 
could cut and sear the wound to prevent bleeding, 
as in removing a part of the tongue, or other or¬ 
gan full of small blood vessels — a most valuable aid 
to the surgeon in many operations. 

The electric light was used in this year upon the 
operatic stage, representing the sun, in the opera of 
“La Prophete.” Two Englishmen, Greener and 
Staite, also at this time patented, perhaps independ¬ 
ently, a lamp on the general principle of Starr’s — 


148 MAKING THE SCIENCE PKACTICAL 


improving the carbon by purifying it and solidifying 
it in an acid bath. But this was an improvement not 
followed up for nearly thirty years — probably be¬ 
cause of the cost of the process, and the difficulties of 
renewing carbons when burned out, as well as the 
lack of means to furnish a strong and steady current 
to many lamps. 

Every year saw new devices brought out for apply¬ 
ing the principles already known, but all were doomed 
to commercial failure because the time was not yet 
ripe for them. Dr. John AV. Draper, of New York, 
experimented with an electric light, Farmer with an 
electric car, in 1847; but neither was the beginning of 
any practical development that requires us to become 
acquainted with their mechanism and principles. 

In 1848, the Morse telegraphic apparatus was 
taken to Germany by two Americans, but they 
could not secure patents, and so had to keep their 
ways of working secret. Professor Houston tells how 
these men were able to telegraph clearly over longer 
circuits than could be covered by the AYheatstone or 
Steinheil systems, and so greatly surprised the Ger¬ 
man experts. Their secret lay in the Morse relay — 
which we have described—and this was kept con¬ 
cealed in a box. They made a line that worked for 
ninety miles, and much mystified the foreign experts. 
Steinheil guessed the secret to lie in the “magic box,” 
and when the relay was explained “ generously ac¬ 
knowledged to Morse the superiority of the latter’s in¬ 
struments over his own” — to quote Houston’s words. 

At this time, or a little earlier, was proposed by 
another inventor, Bain, a telegraph recorder capable 
of much greater speed than any then in use. This 


MAKING THE SCIENCE PRACTICAL 149 


was his “ Chemical Telegraph.’’ It was to use strips 
of perforated paper to send the message — contact be¬ 
ing made whenever a hole came between the key and 
line—and a strip of chemically treated paper to be dis¬ 
colored by the passage of the current in the receiver. 
Both strips being run by clockwork, and many of the 
sending strips being prepared "by a number of op¬ 
erators beforehand, great speed of transmission was 
possible. The paper for receiving could be prepared 
by soaking it in iodide of potassium ; then the electric 
action would cause a brown stain wherever it passed. 
Wheatstone also had an apparatus of the same kind. 

But the ingenious reader will see that with the pos¬ 
sibility of controlling motion and so producing a con¬ 
tact at the end of a telegraph line, any form of 
mechanism could be set in motion and stopped at will. 
The period of wonder was at an end, and the period 
of ingenuity had begun ; or, we may say, discovery 
had been completed, and the principles established. 
The rest was the work of the mechanician. 


CHAPTER XIV 


THE DAYS OF TELEGRAPHY 

Still a new idea was in the telegraph of Bakewell — 
the facsimile telegraph. This was invented from 
1848 to 1850. To understand it we must imagine two 
metal cylinders to be turned at the same rate in two 
stations distant from one another, and kept accurately 
timed, so that their motion is exactly the same. 
Around each is a fine spiral groove filling the surface 
closely from end to end. One cylinder, A, has drawn 
on it in varnish (a non-conductor) a design or drawing 
or writing. The other, B, has a piece of chemically 
prepared paper. Now, let a point be allowed to travel 
in the grove of A, and another in the grove of B, at 
the same rate. The first point is connected with the 
battery, and allows a current to pass whenever it 
touches its cylinder A. The other point rests on the 
chemical paper (a conductor), and causes a stain when¬ 
ever the current comes from A. The design in var¬ 
nish will then break contact whenever the point A 
crosses a varnish line, and will therefore fail to send a 
current. The paper at B will show a stain whenever a 
current has passed or white where it has failed to pass, 
and thus the chemical paper is stained except in the 
lines of the original design, as drawn upon cylinder A. 
These will be reproduced in white, on the stained 
ground. 

The timing of the cylinders can be done either by 
clockwork and pendulum, regulated by electric im- 

150 



THE DAYS OF TELEGBAPHY 


151 


pulses, or both regulated and driven by them. A print¬ 
ing-telegraph, as suggested by Yail in 1837, was in 
a greatly improved form patented by House in 1848; 
but these ideas came to a better form in the Hughes 
Printing Telegraph seven years later, which will be 
spoken of in its place. 

Since 1839 there had been a number of attempts to 
insulate wires so thoroughly that they might be used 
under water, and retain their insulation for a reason¬ 
able time. At first, cotton or hemp wrapping coated 
with asphalt was tried, but the right material was not 
found until 1848, when a gutta-percha coating was 
used. Though a wire so coated and laid between New 
York and Jersey City soon failed for lack of a protect¬ 
ive covering it was the forerunner of the successful 
submarine cables. 

But a principle of the very greatest value to electrical 
development dates from this same year. This was 
an improvement in dynamos. The first suggestion 
of it came in 1845 from Jacob Brett, who spoke of 
using the current set up in the armature to give more 
strength to the permanent field magnets; but the ac¬ 
tual machine accomplishing this was patented in Eng¬ 
land by a Dane, Soren Hjorth of Copenhagen, and 
may have been independently discovered by him. 

He used permanent magnets to excite his armature, 
and then taking a current from the armature sent it 
around smaller electro-magnets that also acted on the 
armature, so increasing the strength of the field cur¬ 
rents, and thereby obtaining better results. This, it 
will be seen, was the introduction of an unnecessary 
link, since the same current that excited the electro¬ 
magnets might have been used to excite field mag- 


152 


THE DAYS OF TELEGEAPHY 


nets originally. The doubling of the field magnets 
was the introduction of more resistance ; but this was 
not to be perceived for some time, and Hjorth at least 
had in his magneto-electric machine the true principle 
of modern dynamos. His invention was probabty 
made not very long before 1855, as his patent was 
dated in that year. The idea of strengthening mag- 



Hjorth’s Dynamo 

A—Armature. C—Permanent magnets. D—Field magnets. G—Commutator. 


netism by using the armature current, however, was 
not yet fully recognized, as we may know from the 
next development of the magneto-electric machine. 
Nollet, Professor of Physics in the Military School at 
Brussels, in 1849 improved the Clarke machine —the 
one that revolved electro-magnets before the sides of 
the permanent magnet poles —but it was by multiply¬ 
ing 1 the number of permanent and electro-magnets 
rather than by using any new principle. 







































































THE DAYS OF TELEGRAPHY 


153 


This new machine was meant to decompose water 
into its gases, and then an illuminating gas was to be 
manufactured. In other words, this machine was a 
device meant to produce gas for gas-lighting, and it 
failed for the simple reason that it cost less to make 
gas from coal. So this machine was put aside for a 
while, to be revived later when the possibility of prac¬ 
tical electric lighting made its power available. 

The middle of the nineteenth century, as will be 
seen, had thus been reached with the science of elec¬ 
tricity well founded. The theories had been well 
studied; a great number of machines invented that 
failed more often because of trade conditions than for 
scientific reasons ; and the work of specialists was well 
begun. Yet everything was in its infancy. The tele¬ 
graph was established as an enterprise, but chiefly for 
short distances on land. The use of electricity as a 
motive power was too expensive and too uncertain to 
compete with steam power. The electric light was 
even less advanced, being little more than a wonder for 
short exhibitions or for use in a few limited fields. 

All the actual outdoor development, the real trade 
and business use was to be brought about in the life- 
time of men still living — such as William Thomson, 
Lord Kelvin. Thus the first submarine cable, between 
Dover and Calais, was in 1850 only a single copper 
wire in gutta-percha, and failed after working for a 
single day ; but in 1851, the next year the same cable 
was relaid as an armored cable and was successful. 
The core of conducting wires was insulated and then 
outside was an armor of wire closely wound to protect 
the insulation from injury. From about the same 
time dates the perfected Ruhmkorff coil, and also the 


154 


THE DAYS OF TELEGRAPHY 


electric locomotive of Page and Yail, a really prac¬ 
tical invention that ran from Washington to Bla- 
densburg, for one mile at the rate of nineteen miles 
an hour; though its motor is now chiefly 


Page’s Electric Motor 

Two soft iron cores were drawn into the coils alternately, the current being 
shifted by a commutator from one to the other, this producing a reciprocating 
movement of the lever. This machine was applied to the first electric locomo¬ 
tive in America. 

notable for being among the predecessors of better 
types. 

All these early motors derived their power from 
voltaic batteries, and zinc cost twenty times as much 
as coal while it produced only an eighth of the 
work for the same weight. In small apparatus, elec¬ 
tricity was proving most valuable. The electric bell, 
for example, invented — so far as the “ trembling ” 
contact is concerned, by Miraud, had come very 
early into general household use. The old style of 
wire and bell-pull was a clumsy and uncertain con¬ 
trivance, as all who remember it will willingly bear 
witness, and the mere fact that the electric wire was 
not moved in ringing the bell, made it immensely bet- 
































THE DAYS OF TELEGRAPHY 


155 


ter. The little Miraud “ Trembler,” was only the 
contact-breaker seen in the Ruhmkorff coil. From 
1852 to 1856 inclusive the chief steps in development 
were in improving the telegraph and the electric 
light. The application of the telegraph to a system 
for giving the alarm of fire was first made by two 
Boston inventors, Channing and Farmer. It was no 
more than an adaptation of the telegraph to a special 
use, being a number of circuits connected with a cen¬ 
tral station. In each circuit, in an iron box was a de¬ 
vice for sending to the central station a signal that 
would indicate where the signal came from. This 
signalling can be done mechanicall} 7 , a lever being 
pulled down against a spring; as the spring returns 
the lever makes electric contacts with points in its 
path so as to ring a bell in the station — and as the 
points are differently arranged, the ringing of the bell 
shows the number of the box from which the message 
comes. The same system is used to-day in the box 
of the district messenger service. 

But an invention, as distinguished from an applica¬ 
tion, was made in the telegraph during 1852-3-4-5 by 
doubling the capacity of the lines. The first sugges¬ 
tion came in the first } 7 ear mentioned, 1852, from 
Moses Farmer, the first practical application of the 
principle being made by Gintl in Amsterdam in 1853 
and 1854, and improvements in the apparatus were 
due to Preece of England, and Frischen and Siemens 
and Halske of Germany during 1855. The practical 
duplex telegraphy, however, was not applied to the 
working lines for several years later, when perfected 
after 1870. The general principle of the duplex ap¬ 
paratus may be here stated, since this principle was 


156 


THE DAYS OF TELEGRAPHY 


discovered at this time, and only failed to work be¬ 
cause of an oversight on the part of the inventors — 
the omission to allow for the electric capacity of the 
line and apparatus — that is, the loss of electricity in 
its working. 

Suppose we wish to “duplex” a line. That means 
to arrange it so that a signal sent from one station A, 
to another station B, shall affect the receiver at B, 
and yet leave the A receiver unaffected; while a sig¬ 
nal sent from B shall affect the A receiver, and notits 
own. This requires some apparatus, for in a single 
line a signal sent from either end would act on the 
whole line, including both receivers unless one or the 
other was shut off. But we want to use both re¬ 
ceivers, independently, at the same time on a single 
line. 

There are two ways of doing this, both by means of 
inserting a relay in the line. One way is to insert 
what is known as the Stearns or neutral relay. This 
is a double wound electro-magnet around which the 
main line v T ire is wound after being divided into two 
branches. One branch is wound from right to left, 
the other from left to right around a bar of the mag¬ 
net. Then half the line is connected to the earth and 
the other half goes to the other station. 

There are now two things to accomplish. First to 
send messages to the distant station without affecting 
the home receiver (or “ sounder ”). Second, to re¬ 
ceive messages without affecting your own use of the 
line. We will examine each separately. 

If you put down your own telegraph-key, closing, 
or making the circuit, the current is formed. It passes 
up to the branch Y and then (by Ohm’s law, the re- 


THE DATS OF TELEGEAPHY 


157 


sistance being made equal) the currents in each branch 
are equal, and one-half goes by the left branch of the 
Y around one-half of the electro-magnet, then down 
into the earth, and is there lost. The other goes, in the 
reverse direction around the other half of the electro¬ 
magnet, and then out by the main line to the other 
station. But the two opposite currents around the 
electro-magnet neutralize each other, so that the elec¬ 
tro-magnet does not act at all on its armature. So far 
as that current is concerned, the magnet is left unaf¬ 
fected, whether current is turned on or shut off by 
your key, and yet half of your current is sent along 
the main line whenever your key makes contact. 

Therefore you can send messages without affecting 
your own “ neutral relay,” and as this relay must act 
to affect your sounder, your own current does not 
move your own sounder. And likewise at the other 
end of the line the other operator’s key will not affect 
his own sounder. But remember that this is done bv 

V 

making the two branches of the Y offer equal resist¬ 
ance, so the current will divide equally on the two 
sides of the relay magnet. 

The next object is to arrange that the current along 
the line will affect the sounder at the distant station. 
Let us follow it. The current arrives first at a coil 
around a half of the electro-magnet winding of the 
other relay, making it exert magnetism. Then it goes 
along the other branch of the Y at the far station to 
the junction of the branches. Here it meets two 
paths. One is up the other branch, and around the other 
half pf the electro magnet. This part of the current 
goes in the same direction around the magnet as in the 
first coil — and so the two coils act together, and at- 


158 


THE DAYS OF TELEGRAPHY 


tract the armature. When the armature is attracted, 
it closes a circuit connecting a new battery with the 
sounder, and the sounder gives a signal. Thus a cur¬ 
rent from the main line inward, moves the sounder, 
while a current outward along the line does not move 
the sounder of the office from which it is sent. 

But we must still account for the rest of the cur¬ 
rent that came from the farther office and did not 
go up the second branch of the Y. This will fill the 
wire down to the key. The key will be either open 
or closed. If open, the current will find a broken cir¬ 
cuit. If closed it will be met by the closed circuit 
sending a current to meet it — a current as yet not 
divided by the Y, and therefore of twice its strength. 
Either way, this remainder of incoming current will 
not act on the relay, to interfere with its signals. 

This explanation of the duplex system is of course 
meant to show only its main principle. The adjusting 
of resistances, and the use of “ condensers ” to make 
provision for surplus current, do not affect the main 
principle and must be explained by technical books. 

All the reader needs to remember is that duplex 
telegraphy in its first and simplest form was accom¬ 
plished by : first, dividing the outgoing current so that 
its halves neutralized each other in opposite winding 
as to the home sounder; and, second, allowing the in¬ 
coming current to act as a whole, since it went in the 
same direction through both coils of the distant 
sounder. Of course it makes no difference, in princi¬ 
ple, whether the current acts directly on a sounder, or 
simply opens and closes a circuit that brings the 
sounder into action. And likewise of the key. This 
too may either close the circuit of the main line, or 


THE DAYS OF TELEGEAPHY 


159 


may close a circuit that closes a switch that makes a 
circuit on the main line. 

Just as in arithmetic the most complicated calcula¬ 
tions come down to the four rules — add, subtract, 
multiply, divide ; so, in electric apparatus, the most 
complicated machines come down to the same simple 
rules, adding current, by making a weak one bring a 
strong one into action (by the relay); subtracting, by 
turning the current into the earth or into a high re¬ 
sistance or making it do work; multiplying, by chang¬ 
ing the tension from low to high (by the induction 
coil, the Leyden jar, and the condenser); dividing, by 
lowering tension, or by separating one heavy current 
into a number of branches. 

Going back now to 1850 we shall find another de¬ 
velopment in the motor, due to Professor G. C. Page of 
the Smithsonian Institution, Washington. This was 
a walking-beam engine, driving a fly-wheel; the beam 
was moved by two coils that attracted alternately 
two core-rods of iron. Attached to the fly-wheel was 
an eccentric rod that moved a commutator, and at the 
right times transferred the current from one coil to 
the other. This motor, run by 100 voltaic cells, was 
the motor-power that ran the engine before mentioned 
from Washington to Bladensburg at a good speed. 
But the jolting interfered with the batteries. 

In 1854 was invented the Siemens armature, first 
designed for use in connection with a telegraph ap¬ 
paratus; but it afterward came to be a most impor¬ 
tant step in the motors and dynamos, of earty days, 
being adopted in the first successful forms. Siemens’ 
armature was made by cutting square edged open 
channels out of a long iron cylinder, and then winding 


160 


THE DAYS OF TELEGRAPHY 


the wire lengthwise in the channels. This form of 
armature was long and narrow, and allowed many 
electric magnets to be put closely along its sides, an evi¬ 
dent advantage in compactness. The same year saw 
the first suggestion of the really practicable form of 
submarine cable — Sir William Thomson having 
suggested the stranded, or rope-wound form. In 



1851, also, came the publication of a article in Z’ Il¬ 
lustration by Charles Bourseul, a Frenchman, which 
is declared by a recent writer to be “ strongly suggest¬ 
ive of the speaking telephone.” But though Bour¬ 
seul spoke of a flexible plate that would vibrate, and 
open and close a circuit, thus causing a distant plate 
to be attracted and released bv an electro magnet, 
there was no description to show that this crude idea 
was put into practice with the many modifications 
necessary to make it repeat sounds like those that 
moved the first plate. It is no more than the first 
crude suggestion of the invention afterward made by 
Reis in 1860. 

In 1855 came a beautiful simplifying of the Daniell 
cell. Instead of separating the two chemical solu¬ 
tions— a weak solution of sulphuric acid and copper 
sulphate — by means of a porous cell, an English in¬ 
ventor, named Yarley, knowing that the copper sul¬ 
phate was heavier in weight than the weak solution of 























The First Telephone 

(See also page 206) 

























































































THE DAYS OF TELEGEAPHY 


161 


sulphuric acid, put it into the glass jar, and then pour¬ 
ing in the weak solution of sulphuric acid allowed it 
to float upon the heavier liquid, as oil will float on 
water or vinegar. Then the copper element was put 
into the bottom of the jar, with crystals of copper sul¬ 
phate, while the zinc was supported above, in the sul¬ 
phuric acid solution, by being hooked on or rested on 
supports across the top of the jar. Thus the principle 
of the Daniell cell was preserved, and the different 
elements and acids separated by their own differing 
weight and position. This was the first “Gravity 



The Gravity Cell 


Cell ” — a modification being in general use to-day in 
telegraph offices. Zinc sulphate and copper sulphate 
are the acids, zinc and copper the electrodes or ele¬ 
ments. While in action, the cell will keep its liquid 
solutions separate, but if not producing current, 
they tend to become mixed together by “ diffusion,” 
—a tendenc} 7 of light and heavy liquids to mingle. 



























CHAPTER XY 

CABLE, STORAGE BATTERY, AND MOTOR 

In this same year, 1855, there were further at¬ 
tempts to popularize the electric light in Paris and 
Lyons. It will be remembered that when the electric 
arc is formed between two carbons, as they burn 
away the space between becomes too wide for the 
current to pass, and the lights go out. Two French¬ 
men of Lyons, Lacassagne and Thiers, patented a 
means for raising the lower carbon as it burned away, 
and gave exhibitions of which enthusiastic accounts 
were printed. But in spite of the enthusiasm, and in 
spite also of the clever mechanism invented by these 
men and others at about the same time, the carbon-arc 
light could not be made a commercial success at the 
time, though it found some use under conditions where 
a brilliant light was desired, and expense as well as 
perfect regularity and equality of lighting were unim¬ 
portant as in theatrical shows, in lighthouses, and in 
the magical lantern. 

There is no space to describe forms that have been 
long discarded, as the arc lamp is still in general use, 
and improved methods of regulating the supply of 
current and length of arc will be explained. More 
important is it to describe the Hughes Printing Tele¬ 
graph, if only to show a machine that is an excellent 
type of the whole class. We have already spoken 
generally of Wheatstone’s. Hughes’s machine re¬ 
quires only one touch to send a letter, instead of three 

162 


CABLE, STOEAGE BATTEEY, AND MOTOB 1G3 

or four on the average, as in the Morse instrument. 
The message is also printed in both sending and re¬ 
ceiving office at the same time — thus checking its 
accuracy. 

The sender is a keyboard like a piano or typewriter 
keyboard. The receiving instrument is a very compli- 



The Hughes Printing Telegraph 


cated apparatus run by clockwork and a weight. This 
is arranged so as to keep time with the other receiver. 
Then, whenever a key is pushed down on the sender, 
it pushes a peg through a hole in a disk revolving hor¬ 
izontally, and thus causes a current to pass just at the 
right moment to press a strip of paper against a type- 
wheel that turns at the same rate as the horizontal 
disk, and prints the chosen letter. 

To describe this complicated apparatus in full is un¬ 
necessary because the ingenuity of the invention is 
almost wholly mechanical rather than electrical. The 

















164 CABLE, STORAGE BATTERY, AND MOTOR 

electrical features presented little that was new, and 
though the apparatus came into extended use in 
America and abroad, and served a good purpose, it 
did not aid directly in the progress of electrical 
science. 

The year 1856 marked an era in the telegraph busi¬ 
ness, being the date of the incorporation of the great 
Western Union Telegraph Company, which was the 
title under which several companies consolidated. In 
1851 over fifty companies were in existence, using 
mainly the Morse system, but also using Bain’s chem¬ 
ical telegraph, and a form of printing-telegraph known 
as House’s. The parent company of the Western 
Union was a company formed in Rochester, New 
York, with the purpose of extending lines westward, 
and it had only limited success ; but its rival com¬ 
panies were by 1854 in even worse shape, their re¬ 
sources being exhausted and their lines nearly in 
ruins. There was but one successful company, which 
operated between Pittsburg and St. Louis on the line 
of commerce from the Southern and Western States to 
the eastern cities. 

The Rochester company succeeded, in acquiring 
cheaply the assets of most of its rivals, and in the 
course of a few years order and enterprise took the 
place of neglect and indifference. New and better 
methods were adopted, the company was incorporated 
by the new name, and the Western Union came into 
existence by act of the New York Legislature on 
April 4, 1856 — just a half century ago. 

During 1857, the Western Union was busy in put¬ 
ting itself into a practicable shape, and meanwhile 
further steps had been taken in the use of submarine 


CABLE, STOBAGE BATTEEY, AND MOTOB 165 

cables. There had been a number laid and used for 
limited distances, and for a short time, and the art of 
insulating them had so far progressed that in 1819 
more than two miles of wire were coated in twenty- 
four hours. The Dover and Calais cable had been 
proved practicable, being six years old, and the theories 
of submarine conductors, thoroughly discussed by 
Faraday and Thomson in 1851, were fairly understood, 
so that the difficulties sure to occur in working long 
cable lines were foreseen, and could be somewhat pro¬ 
vided against. 

Among these difficulties one of the most impor¬ 
tant was the fact that the insulated wire or wires 
within their coating had — like a Leyden jar — a 
great capacity for electricity. The wet outer surface 
was like the outside of a Leyden jar in contact with 
“ earth” ; and so of a charge of electricity sent in at 
one end, part would remain in the cable, held by in¬ 
duction (as in the Leyden jar) and another part of the 
charge would escape from the line since no absolute 
insulator exists — all leak somewhat. All this had 
been worked out mathematically by Thomson — and 
rules were ready for the engineers’ guidance. 

Before the end of 1855, experiments had proved that 
signals could be sent through more than 2,000 miles, 
and a survev of the Atlantic bed between the west- 
ernmost part of Ireland and Newfoundland had shown 
a depth of 1,700 to 2,300 fathoms with a gently undu¬ 
lating plateau most of the way. Shells of the most 
fragile nature were brought up uninjured from the 
depths, showing no disturbance existed. 

A cable was made and in August, 1857, there were 
laid 335 miles successfully — and then the cable broke. 


166 CABLE, STORAGE BATTERY, AND MOTOR 

The fleet had started from Yalentia on the Irish coast 
and consisted of eight vessels, four American and four 
English, and had been out four days. 

In 1858, a better way of stowing the heavy cable 
— ten tons to the mile, was its weight — and better 




Original Atlantic Cable 

i. Protective coating of twisted wire. 2. Gutta Percha. 3. Wrapping 
of thread, soaked in pitch and tallow. 4. Conducting core of seven copper 
wires. 

devices for laying it were adopted and June 10, a sec¬ 
ond start was made, the vessels being the British frig¬ 
ate Agamemnon and the American frigate Niag¬ 
ara, each with a tender. They went to mid-ocean, 
and then separated after splicing the two halves of the 
cable. The cable broke three times, at five miles, 
eighty miles and 300 miles—and then the expedition 
was abandoned until the next month. Again a start 
was made July 17, 1858, and once more the halves 
were spliced and the vessels each turned homeward. 
On August 5, Mr. Cyrus W. Field — <k to whose energy 
and public spirit the enterprise was largely due,” de¬ 
clares the author of “ Progress of Invention in the 
Nineteenth Century” — telegraphed from Trinity 






CABLE, STORAGE BATTERY, AND MOTOR 167 

Bay, Newfoundland, that the cable was laid, and con¬ 
nection made between that place and Valentia in Ire¬ 
land, a distance of 2,134 miles. 

Messages were exchanged between Queen Victoria 
and President Buchanan, conveying mutual congratu¬ 
lations, but so great was public skepticism that it was 
by many thought these were spurious, and only when 
telegraphic news from England had been confirmed 
by letters brought in vessels was the public convinced 
that the cable worked. 

There were in the cable 2,022 miles of wire, and the 
problems presented to the engineers and operators 
were of the most puzzling description, and of com¬ 
plete novelty in detail. The cable was much thicker 
at each shore end, tapered to less than an inch in diam¬ 
eter in the deep-sea portion, and was capable of stand¬ 
ing a strain of over three tons. The induced currents 
were most troublesome, and had to be met by special 
inventions made as the need for them developed by 
experiment. All these difficulties were successfully 
coped with, and the cable transmitted its messages for 
about a month without sign of weakness. But though 
the cable lasted long enough to send a number of im¬ 
portant messages, 366 in all — one preventing the un¬ 
necessary sailing of two Canadian regiments, saving 
$250,000, and another announcing the safe arrival of 
the steamer Enropcu after a collision, saving weeks 
or months of suspense — it lasted hardly more than a 
month, and failed on the day set for Mr. Cyrus Field’s 
New York celebration. 

This cable of 1858 had cost a little over $1,250,000. 
After its failure came a time of delay and renewed 
study of the subject and its difficulties that lasted un- 


168 CABLE, STORAGE BATTERY, ART) MOTOR 

til 1865, about seven years — a delay no doubt ex¬ 
tended bv the war in America. 

The duplex system of telegraphy bad been in 1858 
greatly improved by the inventor Stearns of Bos- 
ton, and abroad the electric light was used in the 
South Foreland Lighthouse—being supplied with cur¬ 
rent by two magneto-electric machines run by a steam 
engine, and employing the carbon arc light. This 
was probably the first use of electricity in lighthouse 
work. 

In 1859 occurred the first use of the electric light 
for household lighting. To accomplish this it was 
necessary to subdivide the current delivered from the 
main, and this was done by Moses Farmer in his own 
home at Salem, Massachusetts. Two years before it 
was announced in the French Academy of Sciences 
that the problem of subdividing the current had been 
accomplished by De Changy, who lighted twelve 
lamps, containing incandescent spirals of platinum, by 
the use of twelve Bunsen cells ; but Professor Houston 
says the lamp was not much used. A similar lamp 
was patented in the United States in 185S by Samuel 
Gardiner and Levi Blossom of New York. All of 
which shows steady work on the problem of electric 
lighting, though successful and permanent lighting had 
to await the general use of the dynamo instead of the 
voltaic cells for supplying the right sort of current. 

A lamp much used in later lighthouse service was 
that of Serrin, in which the two carbons were con¬ 
nected with clockwork run by the weight of the upper 
carbon and its holder. This, by means of a chain and 
pulley raised the lower carbon to meet the upper. 
But this action was controlled by the current passing 


CABLE, STORAGE BATTERY, AND MOTOR 169 


around an electro-magnet. A rather complicated 
mechanism makes the carbons come nearer together 
whenever they burn enough to increase the resistance 
to the current and so weaken the 
action of the magnet. There is 
also a device to insure that the 
arc shall always be in the same 
place, so as to remain in the focus 
of the lenses that permit the rays 
to go out. The apparatus came 
into extensive use, and has “ con¬ 
tributed largely to the success of 
electric lighting,” say Alglave and 
Boulard in The Electric Light. 

But its value depended upon im¬ 
provements in mechanism mainly. 

With 1860 began a new era in 
applications of electricity in dy¬ 
namos and motors, and it is nota¬ 
ble, says Elihu Thomson, for two 
advances of great value and im¬ 
portance. Up to that year electric 
machines yielded currents that al¬ 
ternated rapidly, or if these were 
made continuous they fluctuated 
in strength. The steady cur¬ 
rent like that of the battery could not be long se¬ 
cured. But Dr. Pacinotti of Florence, Italy, in 1860 
described a machine for yielding true continuous cur¬ 
rents. The inventor was only a young student at the 
time, and subsequently, becoming assistant in the 
Astronomical Observatory, turned his attention to 
other sciences. Pacinotti’s machine consisted of two 



Serrin’s Automatic 
Regulator ( 1859 ) 









































170 CABLE, STORAGE BATTERY, AND MOTOR 


electro magnets standing upright, each ending in a 
circular segment so as to inclose most of a circle. 
Within their poles was a ring armature with teeth 
projecting from a centre, and this ring armature was 
set on an axis as a top is — being free to spin about 
within the semicircular poles. Between the teeth of 



Pacinotti’s Machine (18G0) 


the armature are coils of wire all wound the same wav. 

The ends of these coils are fastened to bits of copper 

set into a wooden cylinder on the axis of the armature. 

*/ 

Against these bits of copper a strip of copper is pressed 
successively as the armature turns. The current enters 
the coils of the electro-magnet, and also the coils of 
the armature one by one. Magnetism is set up in the 
magnet, and also in the iron armature, and the machine 
revolves. 

But Pacinotti, in describing the machine, shows that 
if it be revolved by mechanical power, the machine 
will generate electricity. 

Even this machine, however, had its predecessors, 






























CABLE, STORAGE BATTERY, AND MOTOR 171 


for the American inventor Page, in 1852, and a Dutch 
inventor, Elias, in 1812 had designed motors on the 
general principle of modern machines. 

The main importance of the Pacinotti machine is 
the fact that the coils of the armature are all wound 
in the same direction and all connected together in a 
method known at a later date by the name of its im¬ 
prover Gramme. The action of this armature will be 
explained when the Gramme dynamo is described. 



Plante Storage Battery 


The storage of electricity, so-called, dates from 1860, 
when a Frenchman, Gaston Plante invented his stor¬ 
age battery. The general principle on which it was 
based was recognized first about 1801 by another 
French investigator, Gautherot, who discovered that 
wires used in decomposing salted water would retain 


















































































172 CABLE, STORAGE BATTERY, AAD MOTOR 

the power of giving out current for a time after they 
were disconnected. Two years later an investigator 
named Ritter made a “ secondary battery ” from 
plates of copper separated by cloth dampened with 
salt solution, and found it for some time retained, 
after being acted on by a voltaic battery, the power 
to yield a reversed current. De la Rive also found 
evidences of similar possibilities, and secondary cur- 
rents were studied by Faraday, Grove, Wheatstone, 
and other theorists and experimenters. But Plante 
devoted his attention especially to finding what metals 
and chemicals would act most energetically, and was 
able to devise an excellent secondary cell. 

Plante increased the action and made it more lasting 
by winding two sheets of lead spirally about one an¬ 
other, with studs or rubber strips between to keep 
them separated. These sheets were then put into a 
glass jar containing diluted sulphuric acid. In order to 
charge these secondary batteries, they were connected 
for a long time with voltaic cells, and the current 
allowed to pass through the secondary battery in one 
direction. Then the direction of the current was 
changed, and allowed to pass for an equal time oppo¬ 
sitely. The effect of the current is to change the con¬ 
dition of the lead plates. By electrolysis, one plate — 
that connected with the anode — becomes covered 
with a layer of peroxide of lead, while the other — 
connected with the kathode—changed into a spongy 
condition. When the primary cells are disconnected, 
the secondary cells are left in such a condition that 
they are like a new voltaic cell. The peroxide of lead 
is decomposed again, the spongy lead receiving some 
of its oxygen, and electric action being set up by the 


CABLE, STORAGE BATTERY, AND MOTOR 173 

returning of the secondary cell to its original condi¬ 
tion, where both plates are coated with a monoxide of 
lead. 

The reason for reversing the action of the current in 
charging is to improve the secondary effects, perhaps 
by breaking up the surfaces of the lead plates. 

It will be seen that this is in no sense a storage of 
electricity, and the new cell is better called a second¬ 
ary cell, as the voltaic cell acts on a new cell so as to 
turn it into a voltaic cell, it is simply a reversible 
secondary cell. After these Plante cells are charged 
they may be connected in series or in multiple as if 
they were voltaic cells. If it be remembered that the 
resistance offered by the cells of a battery is equal to 
only that of one cell divided by the number of cells 
when connected in multiple (all zinc to all zinc -f- 
all carbon to all carbon) the reader will see that a 
large number of Plante cells should be thus connected 
in charging them so as to reduce resistance. After 
being charged, they can be connected in series, and 
will give a current of much higher electro-motive 
force or tension. 

Sometimes this joining in multiple and then in series 
is done by means of a long commutator rod. Turned 
one way, it connects by means of a strip on each side 
all the zincs, and all the carbons ; which, as the two 
strips are connected, joins the cells in multiple or par¬ 
allel. If the commutator rod be now revolved, a set 
of short bars running through it connect zinc to carbon 
all through, joining the cells in series. Plante ex¬ 
plains that his battery distributed chemical action over 
many secondary cells, for a longer period, so that the 
same action (or its reversing) could be used for a 


174 CABLE, STOEAGE BATTEEY, AND MOTOK 


shorter time with more effect. The development of 
the storage battery (if it must be so called) was slow 
during its first twenty years of life, and then began a 
rapid expansion of its uses. 


CHAPTER XYI 

THE ELECTRICAL FIELD WIDENS 

To this year 1860 that saw the beginning of right 
principles in the armature of dynamos, and the first 
effective storage battery, belongs also the real germ of 
the telephone and a great part of the work that 
spanned the American continent with the tele¬ 
graph. The first telephone was literally that — 
“ far sounder.” Of its precursors are usually men¬ 
tioned the “ magic lvre ” of Wheatstone, but without 
good reason, for Wheatstone’s apparatus was not elec¬ 
trical, being only a rod of wood connecting two sound¬ 
ing boards of two musical instruments. This only 
showed that sound vibrations would travel through a 
connecting material, a fact well known, and illustrated 
by the child’s toy known as the “ lovers’ telephone ” 
— two disks connected by a taut string. In 1837, 
Dr. Page of Salem noted and mentioned that musical 
notes were given when the circuit of an electro mag¬ 
net was made or broken, and also when an armature 
of a motor rapidly revolved in front of the poles. 
Next came Bourseul’s article in the French journal, 
Z’ Illustration, already mentioned, in 1854. 

But telephony was first spoken of by Reis in 
a lecture before a scientific society of Frankfort in 
1861. Johann Philipp Reis was a school-teacher in 
Friedrichsdorf, Germany. He described an apparatus 
in which a membrane moved by sound vibrations was 
made to open and close an electric circuit. The cur- 

175 


176 


THE ELECTRICAL FIELD WIDENS 


rent was created and shut off in a wire leading to and 
acting on a distant electro magnet. The making and 
breaking of the circuit caused the magnet to give out 
sound of a pitch varying with the movement of the 
membrane. 

Speech could not, according to Reis himself, be thus 
reproduced, the consonantal sounds being fairly given 



The Reis Telephone 

Transmitter and receiver. 


but not the vowel elements of words. His idea of 
making and breaking the circuit, as will be seen, was 
not enough to reproduce more than the number of 
vibrations — their qualit}^ was largely lost. Yet, acci¬ 
dentally, words and notes were now and then repro¬ 
duced with clearness; but Reis did not discover how 
to make these accidental effects the usual action of the 
apparatus— which was essential in order that it should 
transmit the human voice and musical compositions. 

It may be admitted as Silvanus P. Thompson as¬ 
serts (quoted by Professor Houston) that Reis’s tel¬ 
ephone was “intended to transmit speech, in his hands 
and that of his contemporaries did transmit speech, 
and will still transmit speech.” But the principle by 
which it acted was not understood, or it would have 
been improved by the surprisingly simple modification 
needed. Reis’s transmitter was a membrane that at 
“ each sound-wave effects an opening and a closing of 










THE ELECTRICAL FIELD WIDENS 


177 


the circuit.” The receiver was a coil of wire through 
which ran a knitting needle resting on two bridges of 
wood on a sounding box. This “ emitted a tone whose 
pitch corresponds to the number of vibrations.” The 
words are Reis’s own. His receiver, as will be seen, 
had no true diaphragm, and I think the reader will 
see that the idea in his mind was entirely different 
from that of the perfected telephone, so far as the re¬ 
ceiver is concerned. But the credit for the first step 
— the transmission of sound by changing it to mechan¬ 
ical motion, and repeating this motion by electric 
transmission to a distance is certainly his. There has 
been much controversy as to how perfectly his tele¬ 
phone transmitted speech, but it seems fair to say that 
the making of the telephone into a practical instru¬ 
ment required several features of which Reis’s appa¬ 
ratus had no trace. 

The transcontinental telegraph line had been de¬ 
manded for several years to connect the systems 
already established on the Atlantic and Pacific coasts. 
Objectors urged that the Indians would take the wires 
and the bison herds would push down the posts. It 
was thought also that the building and maintenance 
of the line would be expensive beyond all reason. Aid 
was asked from Congress, and only $40,000 a year for 
ten years was obtained. The other telegraph compan¬ 
ies believed this inadequate, but the Western Union 
bid for the contract and secured it — being the only 
bidder. 

Ox-teams were hired in great numbers, Brigham 
Young contracted to furnish poles and laborers, and 
an alliance was made with companies on the Pacific 
coast. 


178 


THE ELECTRICAL FIELD WIDENS 


March 15,1861, the line was finished — requiring a 
little over four months — and the greatness of the 
Western Union was begun. 

One more notable advance is credited to that year 
— the beginning of a system of electric units. Mr. Lati¬ 
mer Clark suggested that the unit of resistance in elec¬ 
tric conductors should be named after Ohm, the author 
of Ohm’s Law of Resistance. Professors Gauss and 
Weber had published many papers upon the theory of 
electricity and its measurement, but no short words 
for the various quantities and qualities had been in 
wide use. The British Association therefore appointed 
a committee that entered upon its labors of fixing and 
naming the electric standard units. This work was 
not, however, finally completed until 1869, though 
progressing and reported at intervals. 

The chief electrical events of 1862 were the general 
adoption of arc-lighting for French lighthouses, and 
the installing of a great arc-light at Dungeness light¬ 
house in England ; and also the beginning of a new 
form of electric lamp — again the application of an 
old principle. This was a vapor lamp that sought to 
make use of glowing tubes, exhausted almost to a vac¬ 
uum, through which the current was passed, causing 
glowing lights of varying colors. Though patented, 
it does not seem to have come to practical use, any 
more than did the mercury-vapor lights studied by 
Hawksbee in 1705, or the later investigations of Caven¬ 
dish and Davy into similar effects when electricity 
was passed through the space left by allowing mercury 
to fall in a closed glass tube, producing the Torricellian 
vacuum, — that at the top of a thermometer or barom¬ 
eter tube. Yet ail of these observations were the 


THE ELECTRICAL FIELD WIDENS 


179 


hints of later inventions, that came to fruition when 
followed up. 

In 1863, the chief work recorded is that of the Brit¬ 
ish Association Committee on naming the electrical 
units ; in other words, carrying out the suggestions of 
Gauss and Weber who were the first to recognize the 
great advantage of standards for electrical units, alike 
in theory and in practice. But an account of what 
units were chosen, and their meaning should be given 
only after their general adoption. 

The next year came the suggestion from a French 
engineer, Cazal, that the power of waterfalls might be 
used to operate railways if it were transmitted by 
electricity to the desired location. This idea, as we 
know, was good, but to carry it out required a num¬ 
ber of improvements in the apparatus then known. 
And the same year brought at least one of these — an 
improved motor embodying a most important princi¬ 
ple— the Gramme motor. 

The improvement consisted in the arrangement 
of the rotating armature. The principle was the same 
as used by Page and Pacinotti, but it was applied in 
most convenient form, and gave really continuous cur¬ 
rent, whereas all former machines gave either alter¬ 
nating currents or a rapid succession of currents in 
the same direction —tandem currents, they may be 
called. To recall a little of the more recent history 
of the magneto-electric machines then known, — 
Siemens in 1855 had made the long bobbin-armature 
wound from end to end ; AVilde had used a little 
machine on this plan to excite a big electro magnet 
to make a second bobbin revolve, and had secured 
1,500 revolutions a minute in the main armature. 


ISO 


THE ELECTRICAL FIELD WIDENS 


Next came the Gramme armature. Gramme was a 
Belgian engineer whose invention consisted in using 
for the core of the armature a soft iron ring, placed 
between the horseshoe magnet poles, and in the same 
plane. This turns around its own centre, in that plane 
— as a top spins. 

Being between the magnet poles and within their 



Gramme’s Machine 


The armature A carrying a number of separate sec¬ 
tion coils connected in series, was rotated by hand in 
the first machine. 

influence, this ring has always two poles, each the op¬ 
posite of that of the near pole of the magnet — and 
two neutral points between, on the circumference. 
Round the ring are coiled the insulated wires, in sec¬ 
tion coils wound in the same direction, and connected 
in series, forming a continuous circuit spirally around 




















THE ELECTRICAL FIELD WIDENS 


181 


the ring. Each coil (a part of the main coil) as it 
moves toward the pole of the magnet develops an in¬ 
duced current, stronger as it approaches the pole. 
Then as it passes this current decreases, but as the 
other end of this little section is now toioard the mag¬ 
net pole, the current is in the same direction as before. 
Another coil’follows, the same action is repeated, and 
so on — the current being always in one direction. 
But the other half of the coils are meantime being in¬ 
fluenced in just the opposite way, as we shall see. 
Suppose as they go around, the coils are proceeding 
north-pole end forward. Then considering any one 
coil we shall have it approaching its north pole to 
the south pole of the magnet; it passes, and then has 
its south pole toward the south pole of the magnet. 
At the beginning of the second half of its revolution, 
it is approaching with its north pole toward the north 
pole of the magnet, then passes and has its south pole 
toward the north pole of the magnet. 

But as the armature is turned, currents are created. 
The first half revolution first brings unlike poles to¬ 
gether, and then separates like poles; the second half 
revolution first brings like poles together, then sepa¬ 
rates unlike poles. Thus, by Lenz’s law, the two 
induced currents are in opposite directions; but each 
being continuous and uninterrupted, they are united by 
two commutators into a single continuous current. 

Of course it must be understood that we can only 
give the action in the very crudest and simplest form, 
in order that it may be understood. But the Gramme 
armature was the beginning of an enormous improve¬ 
ment in these magneto-electric machines that preceded 
dynamos and motors. 


182 


THE ELECTRICAL FIELD WIDENS 


In the next year, 1865, came a great improvement in 
another form of electric machine — of the class de¬ 
veloped from Yon Guericke’s sulphur globe, Newton’s 
glass globe, and the frictional machines that followed 
in the eighteenth century. These had, though bet¬ 
tered, remained in essence the same machine Ramsden 
invented — a glass disk with rubbers, collecting points, 
prime conductor, and all. There had come in 1775 
Volta’s electrophorus — the resinous cake already de¬ 
scribed. But now came a long step forward — made 
in a way that seems almost inevitable in all machines. 
Instead of a plate applied to another plate, and lifted 
— reciprocating motion — there was to be circular 
motion applied to the same purpose. Earlier experi¬ 
menters had improved on the crude electrophorus, but 
though some of them (Darwin and Nicholson being 
named in the “ Britannica ”) used rotary motion, the 
purpose was not fully followed out. But in 1860, 
Yarley devised an electric machine the principle of 
which was excellent. It consisted of an insulating 
disk bearing on its edge or circumference conductors 
or electricity carriers. These at opposite ends of a 
diameter pass into two hollow conductor-cylinders slit 
to receive the carriers. 

Inside each cylinder are two metallic springs, one 
connected to the cylinder, the other connected to 
earth. Supposing a small positive charge to be in one 
cylinder, as a carrier is revolved into that cylinder, it 
receives the charge, and, like the electrophorus plate, 
being touched by the earth-connecting spring, carries 
away a negative charge until it comes to the other 
cylinder, where being inside a hollow conductor it 
gives up the charge to that conductor through its 


THE ELECTRICAL FIELD WIDENS 


183 


spring. Then it receives a positive charge at the 
other spring, and goes on to the first cylinder again. 

In short, the apparatus amounts to having a number 
of little electrophoruses on the edge of a disk, so 
arranged as to be charged and discharged by the cyl¬ 
inders— the strength of the charges always increasing 
by accumulating. 

This is the principle of the “ induction machine.” 
And it was soon greatly improved in form. The 
“ most remarkable as well as the most useful of these 
machines ” is that made by Holtz. 

Holtz’s induction machine has two glass disks set 
closely side b} r side and upright, one fixed, the other 
rotated. The fixed plate is slightly larger, and this 
fixed plate has cut through it two holes at the ends of 
a diameter, back of each being glued pieces of paper, 
with blunt “ tongues ” extending through the holes 
and nearly touching the moving plate, which rotates 
opposite to the pointing of the tongues. These pieces 
of paper collect current, and opposite them are brass 
rods ending in balls, but having comb-points toward 
the papers. These brass rods slide in holders. 

The balls on the rods being brought into contact, a 
rubbed rod of ebonite is touched to one, giving a nega¬ 
tive charge. Then they are separated, and the rotating 
wheel is turned. A positive charge is induced in the 
wheel, is taken off by the points, and is shown by 
sparks between the separated ball-ends. 

This machine is hard to explain in every detail 
without diagrams, but the principle of it can be under¬ 
stood without that, for it is the same as the little 
electrophorus. The negative charge induces a positive 
charge in the other brass rod. This escapes by the 


184 


THE ELECTRICAL FIELD WIDENS 


points to the paper, by the tongue of the paper to the 
wheel, is carried round to the other tongue, where it 
makes the other paper positive, which induces a nega¬ 
tive charge in the first rod — and thus the accumula¬ 
tion goes on increasing, except (a very important 
exception) the losses into the air which must be 
greater as the tension (the pressure, or the electric 
potential) increases. 

An increase of the number of disks and so on, makes 
more and more powerful machines, enabling very long 
sparks to be sent between the rods, or enabling heavy 
charges to be collected in Leyden jars or condensers. 
Such a multiplied Holtz machine is the Wimshurst 
Influence Machine, but it is also made simpler. 1 It has 
two plates of glass covered with shellac, and revolving 
in opposite directions. Both carry strips of tin foil 
glued on radially. These are touched by brushes, 
that conduct away the induced charges. The brushes 
are connected with the rods or electrodes. Practically 
there is always some little electric charge in the tin- 
foil strips, and as these are revolved, the brushes con¬ 
duct away the charges on the two opposite plates, so 
that a difference of potential arises and is constantly 
increased as before. 

This difference of electric state — difference of po¬ 
tential — is what causes the passing of the electric cur¬ 
rent from one thing to another, and these influence 
machines are mechanical contrivances for increasing a 
small difference. It is as if there was a slight differ- 
ence of level between two pools of water in the course 
of a stream. By removing water from the lower, we 


1 See illustration on page 52. 


THE ELECTKICAL FIELD WIDENS 


185 


increase the difference of level, and more water flows. 
Or suppose a tank connected with another tank by a 
pipe connecting them at the bottom, and suppose the 
first tank to be supplied by apparatus that flows the 
faster as the tank is emptied. Then we drive a spigot 
into the second tank. As the water flows out, there 
is a difference of pressure, the first tank begins to flow 
to the second, then the first tank receives a supply 
from the apparatus for filling it, and so on. This is 
like the induction machines. 

In the great advance of electrical science, the trans- 
Atlantic cable was never forgotten. 

Despite the failure of the first Atlantic cable after 
it had transmitted messages for a short time, and 
the general apathy toward renewing the enterprise, 
Mr. Cyrus Field and his British backers had by no 
means abandoned it. 

The British Board of trade having appointed a 
committee of eminent engineers to report on the mat¬ 
ter and having received in 1863 a favorable report, 
the capital was secured to renew the attempt to lay a 
permanent cable. July 15, 1865, saw the sailing of 
the Great Eastern with a new cable between three 
and four times as large as that of 1858. 

There were slight delays and troubles at first but 
they were remedied. One deserves mention. Twice 
a short piece of wire was found to be driven through 
the insulation by some scoundrel — probably to cause 
a fall in the price of the cable company’s stock. The 
cable had been laid to a distance of a thousand miles 
and more when it broke and sank. It was grappled, 
raised, but fell again to the bottom, and had to be 
abandoned for the year — a loss of $3,000,000. 


186 


THE ELECTRICAL FIELD WIDENS 


This subject of cable-laying deserves a book to itself, 
for it is a most notable combination of human learn¬ 
ing, engineering skill, and brave seamanship ; but we 
are mainty concerned with the electric problems aris¬ 
ing after the cable is laid successfully. 

In 1865 Clerk Maxwell, whose researches upon elec¬ 
tricity have been as fruitful as those of any investiga¬ 
tor unless it be Faraday, announced a theory that 
light is an electric disturbance in the ether — an 
opinion that was remarkable at the time, but is now 
generally accepted, and considered as no more than a 
special case under a more general law including the 
phenomena of heat, light, electricity and radio-activ¬ 
ity. It cannot be discussed here, since it has been so 
much more developed in our own time. Another dis¬ 
covery of this same period, about 1866, was also to be 
used later. Varley, of whose cell we have spoken, no¬ 
ticed the resistance offered to an electric current by a 
mass of filings until the current was established, and 
explained it by the setting up of conducting paths as 
the filings were electrified and attracted one another. 
This observation was to prove of great use afterward 
in wireless telegraphy, as will be seen. 


CHAPTER XVII 


CABLE, DUPLEX, AXD DYXAMO 

Three happenings of 1866 were to help greatly the 
advance of electric science — the consolidation of sev¬ 
eral smaller companies with the Western Union, 
bringing together a large amount of capital interested 
in telegraphy and kindred subjects, the successful com¬ 
pletion of the Atlantic cable, after so many trials and 
tribulations, and the invention of a still better electric 
machine by Wilde. 

The Western Union by the absorption of the Ameri¬ 
can Telegraph Company and the United States Tele¬ 
graph Company became a well centralized powerful 
corporation with the management located in New 
York City, and owning 75,000 miles of wire, operating 
2,250 offices, and sending between four and five mil¬ 
lion messages a year. 

The final successful Atlantic cable expedition left 
England in 1866, the Great Eastern again being 
used. On the 13th of July the voyage began, and on 
the 28th the ocean cable was spliced to the shore end 
at Newfoundland, and once more America and Europe 
were joined, this time with a bond destined to endure 
for long service. The delight of the engineers and 
their brave helpers may be brought nearer to our un¬ 
derstanding by reading this extract from the diary of 
Sir Daniel Gooch, the English engineer, expressing his 
feelings on making the successful landing in New¬ 
foundland in July, 1866: “ Is it wrong that I should 

187 


188 CABLE, DUPLEX, AXD DYXAMO 

have felt as though my heart would burst when that 
end of our long line touched the shore amid the boom¬ 
ing of cannon, the wild, half-mad cheers and shouts of 
the men ? It seemed more than I could bear. IIow 
many anxious hours has the realization of this day 
cost me; yet I am rewarded. I am given a never- 



The Great Eastern Laying the Atlantic Cable ( 1866 ) 


dying thought: ‘ That I aided in laying the Atlantic 
cable.’ . . . When the cable was landed at Heart’s 

Content there was the wildest excitement I had ever 
witnessed. The old cable hands seemed as though 
they could eat the end ; one man actually put it into 
his mouth and sucked it. They held it up and danced 
round it, cheering at the top of their voices. It was 
a strange sight — nay, a sight that filled oure}^es with 
tears. Yes, I felt not less than they did. I did cheer : 
but I could better have silently cried.” 

It is an interesting fact, and one not unimportant in 
regard to its electrical bearings that, while making ex¬ 
periments in regard to the least quantity of current 













189 


CABLE, DUPLEX, AND DYNAMO 

that would operate the receiving instrument at the 
other end of the Atlantic cable, an English operator 
at Valentia in Ireland made a voltaic cell out of a 
lady’s silver thimble, using only a little acidulated 
water and probably a tiny bit of zinc — though the 
zinc is not mentioned in the article (from the Elec¬ 
trical World). This little cell was able to give cur¬ 
rent enough to operate the cable ; but we must not 
forget that the difference of potential is what causes 
the current, and this is as great in a tiny cell as in a 
big one— the little one is less only in volume of cur¬ 
rent. 

The operator at the American end of the line next 
took his turn in microscopic cell-making. He used 
an old percussion cap — of which a dozen might go 
into a thimble — looped a fine copper wire about it, 
fastened a minute strip of zinc to another copper wire. 
A drop of acidulated water filled the gun-cap cell, the 
end of the zinc was inserted, connection made with 
the cable and the earth, and signals were transmitted. 

It is said that the English operator at the other end 
reported the signals as “ awfully small,” but the bat¬ 
tery did its work across the 2,000 miles. The Ameri¬ 
can operator at Heart’s Content, Newfoundland, was 
William Dickerson, of the Anglo-American Telegraph 
Company ; and he afterward gave the tiny battery to 
IT. II. Ward, of the Western Union. Perhaps the 
greatest wonder of the occurrence is the perfection of 
the cable and its instruments. 

The third achievement of 1866 was Wilde’s electric 
machine, which used a small machine with permanent 
magnets to excite electro field magnets; thus adopting 
Hjorth’s principle of eleven years earlier, and be- 


190 CABLE, DUPLEX, AXD DYNAMO 

coming the forerunner of the self-exciting type of 
dynamos. Wilde also made later a triple machine, 
using a small permanent magnet machine ( or as it is 
generally called, a “ magneto machine ”) to magnetize 
the electro-magnet of a larger machine, which in turn 
magnetized a third electro-magnet. 

Guillemin says that this required an engine of 
fifteen horse power to put it in movement, but yielded 
an enormously strong current, melting a heavy bar of 
platinum. 

But in December of 1866, Yarley patented a 
machine that did away with Wilde's u exciter” or 
permanent magnet — thus divorcing the permanent 
magnet from the dynamo. Yarley, Wheatstone, Moses 
G. Farmer and Dr. Werner Siemens at about the same 
period seem to have hit upon the idea that the elec¬ 
tric machine contained enough difference of potential 
to magnetize its own magnet from the beginning. At 
all events, in 1867, machines on this principle were made 
by all three or patents taken out. All had discovered 
that if the armature was set spinning, as it cuts the 
lines of force coming from the electro-magnet — no 
matter how weak these may be, — currents are caused 
in the armature coils, are transmitted through the 
electro-magnet coils, and a “ building-up process ” takes 
place. Soon a high degree of magnetizing is accom¬ 
plished, and when the dynamo is fully charged, it runs 
with great resistance, furnishing a strong current, 
precisely as if a permanent magnet starter had been 
employed. 

It will be seen that this self-exciting is done by con¬ 
necting the armature coils with the electro-magnet 
coils, and using the armature current to produce mag- 


191 


CABLE, DUPLEX, AND DYNAMO 


netism. But this can be done in three ways : (1) All 
the current can be passed around the magnet. 
(2) Part of the current can be taken around the mag- 



Direct Current Dynamos 

A—Series-wound. B—Shunt-wound. C—Compound-wound. 

The armature revolves between the pole-pieces, marked plus and minus. The heavy 
dotted lines indicate the external circuit which takes its current from the commutator. 


net. (3) Sometimes all and sometimes part can be 
used. These three forms are known by the names, 
series-wound ; shunt-wound ; compound-wound. Three 
kinds of windings accomplish these results. 

































































































192 


CABLE, DUPLEX, AND DYNAMO 

Suppose the current from the dynamo is to go to a 
set of arc-lights. Then, if we connect the armature 
coils-first to the coils of the magnet, conducting the . 
whole current around it, and then to the lighting sys¬ 
tem, we have a series-wound dynamo. If we connect 
the armature coils first with the lighting system, and 
then let a side connecting wire run to the coils of the 
magnet, we have a shunt-wound dynamo. If we take 
a series-wound dynamo, and then add the shunt wire, 
so we may use either or both, we have the compound- 
wound dynamo. 

Each of these forms of dynamo has its own advan¬ 
tages and disadvantages, and is adapted to special 
uses. 

In 1869 came the report of the committee appointed 
by the British Association to fix and name the Stand¬ 
ard Electrical Units but the final adoption of a 
uniform international system did not come until 1881. 

In 1872 the duplex telegraph was perfected by 
Joseph B. Stearns, of Boston, being covered by two 
patents issued in that year, which set Thomas A. Edi¬ 
son to work upon an improvement of the system. 

Edison was at this time twenty-five years old. Born 
in 1847, in Ohio, he became at twelve a train-boy, and 
at fifteen printed a small paper on the train, cir¬ 
culating it among the employees. Having saved the 
life of a child, he was taught telegraphy by the father 
and became an operator. At seventeen he invented 
an automatic telegraphic repeater, for transmitting a 
message to another line. But for so active a brain the 
confinement of the teleg*raph-key was unbearable, and 
he became known as a skilful but nomadic “ tramp ” 
operator. 


193 


CABLE, DUPLEX, AND DYNAMO 

His success came to him. as the result of inventing a 
commercial stock indicator which he sold for $40,000; 
and with this money he established his first labora¬ 
tory at Newark, New Jersey, and began his career as 
a professional investigator and inventor. 

In 1873 there was an industrial exhibition in 
Vienna and among the exhibits were a number of 
machines including a magnetic motor and a Gramme 
dynamo, arranged in a group so that there might be 



Duplex Telegraphy—Stearns-Edison Method 

At A and B are the receiving and transmitting instruments, differentially wound, one 
coil of A being connected to that of B, while the other is connected with the rheostat 
R and R. If then both keys are simultaneously depressed, the currents sent will 
strengthen each other. If only A be depressed the current will branch at e, dividing 
equally between the differential coils at A, and causing no deflection of the needle. 
At B. however, the current can only pass through one of the windings, and thus make a 
signal at B. The letters C Z show the battery connections. 

shown examples of their various uses as generators of 
electric currents and in working machinery. Some 
were to be run by a number of belts from an engine- 
shaft. Then occurred one of those accidents that 
properly observed and used lead to industrial progress. 
A workman happened to attach two wires from a 
running dynamo to the magneto-electric machine that 
had not yet been set in operation by the belting from 
the engine-shaft. To the workman’s surprise the idle 
machine at once began running backward at great 
speed. Gramme, the inventor, was summoned, and he 
















194 CABLE, DUPLEX, AND DYXAMO 

at once saw that the second dynamo had been made a 

w,otor. 

Now this was not precisely a new discovery, for as 
Professor Houston points out it was “certainly known 
to Lenz in 1838 ” that the same machine would act 
either as dynamo to produce the current when run by 
power, or power ('mechanical motion) when set in 
revolution by a current. Jacobi in 1848 also knew this, 
and Pacinotti, the Italian, mentioned it, as did 
Siemens in 1867. But something was needed to show 
the principle clearly and publicly, and this happening 
at the Vienna exhibition — whether accidental, or, as 
one account makes it, the result of an ingenious at¬ 
tempt to make up for the failure of two batteries to work 
the magneto-electric engine—was a public demon¬ 
stration that the current from a dynamo could be 
readily conveyed to another dynamo and would make 
it into an efficient motor. 

The story that the connection of the two was not 
accidental is given in Houston’s “Electricity in 
Every Day Life,” and seems the more probable for this 
reason : Fontaine who made the connection says that 
the connecting was done by means of a conducting 
cable 250 metres in length, — and that notwithstand¬ 
ing the resistance of this long conductor, the second 
machine was set into so rapid a revolution as to work 
the pump attached to it much too violently. Fontaine 
therefore interposed still more cable — over two 
kilometres — to increase resistance and thus decrease 
the speed. 

This proof of the Gramme dynamo’s power to work 
another dynamo through a long conductor seemed to 
be just the demonstration needed to set inventors to 


195 


CABLE, DUPLEX, AXD DYNAMO 

work upon using so convenient a means of conveying 
power to a distance — which, then at least, owing to 
the lack of economy of motors as compared to steam- 
engines, would be the chief reason for perfecting the s 
motor-use of dynamos. The principle, in short, was 
not new, but its practical application on an industrial 
scale was first clearly shown in June, 1873, and thus 
became a distinct step in the evolution of electrical 
arts, for it at once led to projects for electric-transmis¬ 
sion of power on a large scale, and especially to rail¬ 
way propulsion. 

The quadruplex system of telegraphing was invented 
and brought out by Edison in 1874. This allowed 
two messages to be sent each way at a time over one 
wire. But in order to understand this there is a miss¬ 
ing link to be supplied. Duplex telegraphy we have 
explained as the sending of two opposite messages on 
the same wire at one time, and, it will be remem¬ 
bered, is done by dividing the current. “ Diplex ” 
telegraphy, on the other hand, is the sending of two 
messages at one time in the same direction on one wire. 
As quadruplex telegraphy combines these two, diplex 
telegraphy must first be understood. It was first 
worked at by Dr. J. B. Stark of Vienna, and then im¬ 
proved by others, but finally brought to success by 
Edison. The principle of diplex is to have at the far 
end of the line two receivers, one worked by strong 
currents only, the other responding only to a positive 
(or a negative) current, and being unaffected by the 
other. 

As to the strong and weak current receiver, it is so 
arranged with resisting springs that it is not affected 
by the weak current; for this is not strong enough to 


196 


CABLE, DUPLEX, AND DYNAMO 

operate the relay that works the receiver. Only 
when a strong current moves the relay armature is the 
circuit to the receiver closed so it will receive the sig¬ 
nal. 

The other form of receiver has a polarized relay 
(invented by Siemens) that will respond only to (say) 
the positive current, while the negative current does 
not move it. This relay consists of an electro-magnet 
wound in opposite directions on the two poles, so that 
the} 7 have their ends both of the same polarity. Be- 



Diagram of Diplex Principle 

A and B use polarizing keys. C and D use strengthening keys. 

tween them is a steel bar, also magnetized, but with 
polarity opposite to that of the electro-magnet poles. 
It is thus attracted by both equally —and is free to 
swing toward either being pivoted like a compass 
needle. Upon the passage of a positive current one of 
the poles of the electro-magnet is strengthened, and 
the other weakened (their coiling being opposite), and 
the steel-bar moves toward the strengthened pole. 
Now if we put a stop to the bar on one side, leaving 
it free to move only toward the other — it will respond 
only to the current that strengthens one side. There¬ 
fore, by putting an obstruction between the bar and 
the pole that would be strengthened by a negative 
current, we can stop its tendency to move that way, 
and yet leave it free to be attracted whenever a posi¬ 
tive current is sent. 






CABLE, DUPLEX, AND DYNAMO 


197 


This relay is often mounted upon a permanent steel 
magnet shaped like a capital C — the bar being 
hinged to the upper pole, and the electro-magnet 
being set on the lower. The permanent magnet 
helps the balanced state, strengthening both the 
polarity of the electro-magnet and that of the steel 
bar, without interfering with their response to the 
arriving currents. 

The transmitter to this form of relay is a key 
known as a “pole-changer,” so arranged that it sends 
one direction of current when pressed down, the other 
when raised by a spring. 

The polarized relay is made sensitive enough to re¬ 
spond to the positive weaker current used by the 
other operator ( the u strong and weak ” transmitter ) 
but acts with either strong or weak positive current. 
So both the polarizing key, and the strong and weak 
kev can send their signals without interference with 
each other. Through the line there is always some 
current passing. One operator is able to strengthen 
or weaken it at will by his key, and thus send his 
signal; the other cannot either strengthen or 
weaken it, as his key merely makes it positive (signal¬ 
ing) or negative (non-signaling). Of course the 
polarized relay can be prepared beforehand to respond 
to either the negative or positive current at will. 

This in an uncomplicated form is the general idea of 
the way in which diplex telegraphy is accomplished. 

There is also another form of duplex than that 
already described. This second form is based upon 
the employment of what is known as Wheatstone’s 
Bridge —• a device for measuring electric resistance of 
conductors. This “ bridge ” was invented by Christie, 


198 


CABLE, DUPLEX, AXD DYXAMO 


and its use introduced by Wheatstone. Suppose we 
make a diamond-shaped line of conducting wires — that 
is, a parallelogram like the diamond spot on playing 
cards. From one point to another opposite we attach 
another wire, thus making two triangles joined at 
their bases thus : <1[> Then we connect the two wires 
of a battery at the ends thus : -<!i>- so a current flows 
through all the wires. Now we put a galvanometer 
inside the diamond and connect it to the ends of the 
transverse wire which is cut in the middle. Then 
the resistance of the two sides of the diamond —the 
upper and lower — being adjusted and made equal 
there is no current through the galvanometer, because 



K—Transmitting keys. R—Receiver 

current flows only where there is difference of poten¬ 
tial. The adjusting can be done by putting thicker or 
thinner wire in the circuits. Now if we put in a piece of 
wire or connect at one quarter of the circuit some appa¬ 
ratus of which we wish to know the resistance, we 
try to restore the equality by balancing with known 
resistances put in the other corresponding quarter of 
the circuit. For example, we put a coil of insulated 
wire into the left half of the upper circuit, and And 
that it disturbs the galvanometer, since there is now 
more resistance in the upper half, and the potentials 
being different current flows from the higher to the 











199 


CABLE, DUPLEX, AXD DYNAMO 

lower potential. We then put into the left half of 
the lower circuit wire lengths of different known 
(tested) resistances. When we have balanced the two 
halves the galvanometer will cease to show current, 
and we shall know the resistance of the insulated 
wire. 

It is evident from considering this bridge or balance 
that it gives us a means of passing an electric current 
around a galvanometer without affecting it so long as 
the resistance of the two paths are kept equal in po¬ 
tential. If now we put a receiver of a telegraph line 
in place of the galvanometer, it also will be unaffected 
so long as the two diverging paths offer equal resist¬ 
ance and so are of equal potential. This is adapted to 
duplex telegraphing. Let the line from the sending 
station be divided by such a bridge with the 
home receiving instrument set in between the paths. 
Then the outgoing current will not affect that receiver, 
for half the current goes to the line on one side of it, 
and the other half goes to the earth on the other side, 
balancing that current. But the outgoing current 
when it reaches the other end of the line, goes inward 
past the bridge, and then to earth, passing the bridge 
in the other direction, and making a difference of 
electric potential. This causes a current in the far 
receiver. 

Whether the far key current is turned on or off 
will make no difference, for it is either absent, or even 
at the bridge ends of its own receiver, and has no 
effect. 

Now to apply all this to quadruplex teleg¬ 
raphy. First it may be said broadly that the duplex 
(either system) and diplex do not interfere, and so 


200 


CABLE, DUPLEX, AXD DYNAMO 

may be combined. The duplex simply divides the cur¬ 
rent into halves, and makes these balance at home, 
while not balancing at the far station. Strong or 
weak currents may be equally well divided. The 
strengthening or weakening of the current, and the 
change of polarity of current may all be done as well 
with the half current. Therefore in the quadruplex 
we have in each station operators diplexing their own 
currents ; and as regards the other two operators, their 
currents are duplexing. Thus we have A using 
polarity of current at his station ; B using the same 
system and duplexing with A. C is with A, but is 
using only a strong current, thus diplexing with A. 
D is with B, also using only the strong current, and 
duplexing with C. Thus each operator is diplexed 
with his companion, and duplexed with his corre¬ 
spondent — all four can send messages at once by the 
same wire. 

Of course the two receivers at each office are each 
attended by receiving operators — making four men 
in each office, all using one wire, and so the service is 
quadrupled, the wire used fourfold, and the line 
said to be quadruplexed. 

The credit of making this system a practical every¬ 
day working system belongs to Thomas A. Edison, 
and his invention was made in 1874. 

It is not pretended that the foregoing explanation 
will make the whole working of a quadruplexed line 
clear, but at least it will set forth the principle, and a 
study of the instruments at work will complete the 
knowledge. 



The Telegraphoxe 

By courtesy of The Sterling Debenture Co. 
(See also page 302) 












CHAPTER XVIII 

CABLE RECORDER, TELEPHONE, AND 
ELECTRIC LIGHT 


The problem of transmitting signals by a circuit 
such as the Atlantic cable is of course one entirely 
different from that presented by the land lines. In 
the land lines relays can be brought into play 
wherever needed, but the cable must be worked from 
end to end with a single force. The capacity of a 
cable is enormous, and all this capacity must be sup¬ 
plied before there is any action — any electromotive 
force — at the further end. 

To some extent the problem had been worked out 
beforehand, but actual experience required some 
changes in the theory. The various trials of methods 
resulted in the general use of the mirror galva¬ 
nometer — a modification of the old device used by 
Gauss and Weber in their telegraph in Gottingen. 
During 1858, for the one month’s life of the first 
Atlantic cable, a mirror galvanometer as improved by 
Sir William Thomson was used as the receiver, and a 
still better form of the same instrument was used on 
the cable of 1866 and later. 

This is an application of the deflected needle princi¬ 
ple of Oersted, the apparatus being made as sensitive 
as possible. 

Two magnetic needles are connected by a rigid 
frame with their poles in opposite directions, so they 
have no tendency to point any way more than another. 
This needle-pair is hung by a silk fibre, and attached 

201 


202 TELEPHONE AND ELECTEIC LIGHT 


to each of the needles is a tiny mirror. Then a 
coil of wire is wound into the “shape and position of 
a vertical figure 8 ” (to quote from Tunzelmann’s 
“Electricity in Modern Life”). This is made of very 
fine silk wound copper wire, so as to give many turns. 
If a current goes through the coil, each loop of the 8 
acts on one needle, and tends to turn both in the same 
direction—either both in one direction or both in 
the other — as the current is positive or negative. 
This is called an astatic galvanometer. 



A Form of Mirror Galvanometer, as Constructed 
by Sir William Thompson 

The light from the lamp, placed before a slot in the screen, is re¬ 
flected from a mirror, attached to the galvanometer-needle, the light 
thus being thrown back to the scale, at the right, and the signals being 
read by the movements of the spot of light, as it is deflected to the 
right or left by the swinging of the needle. 

This enables the sending operator to turn the 
needles one way or the other, at will. As they turn 
they move their little mirrors, and these reflect a beam 
of light so that it is moved upon a scale — greatly 
increasing the slight motion of the mirrors. These 
are the essential parts of the apparatus. 

As to the transmitter, it has two keys. One con- 









TELEPHONE AND ELECTRIC LIGHT 203 


nects the cable and the positive pole of a battery, 
when pressed ; the other connects the cable and the 
negative pole, when pressed. When either is not 
pressed, it connects with the earth. Consequently the 
operator can send into the cable either a positive or 
negative current. One turns the needles in one 
direction, the other in the opposite; and by watching 
the motion of the beam of light, that is, the moving 
spot of light on the scale, the message is read, for 
right and left correspond to the dot and dash of the 
Morse alphabet. 

This form of apparatus is adopted for several rea¬ 
sons. First, because it is highly sensitive, acting even 
when only feeble currents are transmitted. Second, 
because signals by means of a non-reversed current — 
as given by only making and breaking circuit— would 
be far too slow. A long condenser like the cable, 
fills and empties slowly, and between each make and 
break, a long pause would be required while the cable 
cleared itself. The reversing helps the clearing 
greatly, though still the cable works more slowly than 
a short land line. Third, weaker currents will do the 
work with these instruments, and there is less danger 
of harming the cable’s insulation if weaker currents 
are used. Fourth, the weaker the current employed, 
the sooner will the charge it sends into the cable be 

cleared when circuit is broken, or when the current is 

\ 

reversed. All these reasons explain why the ordinary 
instruments have been replaced by more delicate 
devices when the signals must be sent by means of a 
long submarine cable. 

Both the cable transmitter and receiver have been 
improved by Sir William Thomson. He made the 


204 TELEPHONE AND ELECTRIC LIGHT 


transmitter automatic, operating it by a punched 
paper strip that exactly adapted the signals to the 
action of the cable, and attached to the receiver a 
device for recording its signals. This is known as the 
siphon-recorder, invented in 1874 — or patented then 
— “the most important invention relating to subma¬ 
rine telegraphs,” as the author of “ Progress of Inven¬ 
tion in the Nineteenth Century ” says. This is a light 
coil of wire so hung between the poles of an electro 




The Siphon-Recorder and Its Record 

C—Coil. S—Siphon. (The record spells the words “ Siphon- 
Recorder.” 


magnet as to be moved by the current coming through 
the coil from the cable. As the coil moves, it moves 
to and fro a light glass siphon that dips into a little 
box of ink, and this siphon almost touches a ribbon of 
paper moved below it. As the current comes and 
moves the coil it also moves the siphon by means of a 
connecting thread, and so makes a wave line. Thomson 
oppositely electrified the paper and siphon, so that the 





































TELEPHONE AND ELECTRIC LIGHT 205 


attraction between paper and ink caused the mark; 
but a later inventor, Cuttriss, vibrated the siphon by 
electro magnetism, thus causing the ink to leave the 
end and this was an improvement on Thomson’s ap¬ 
paratus, which tended to lose its electric charges in 
damp weather. To have siphon and paper touch 
would cause friction, and interfere with the movement 
of the coil. 

If it be added that cables can be duplexed like land¬ 
lines, except that the exact balancing is much more 
delicate, we shall have brought the art of cable- 
telegraphy up to the date we have now reached. 
Diplexing and quadruplexing have not been accom¬ 
plished with the weak cable currents. 

In the beginning of 1876 occurred a remarkable 
instance of simultaneous invention. On February 14, 
within two hours, were filed two preliminary papers 
for telephone patents, one being in the name of Elisha 
Gray, the other in that of Alexander Graham Bell. 
Gray filed a caveat, Bell an application for a patent. 
Into the almost endless controversy that raged about 
the telephone invention he may enter who chooses to 
consult the special literature of the subject. It is 
enough for our purposes that to Bell was awarded the 
final victory, and to him seems to be due the really 
important features that produced the modern tele¬ 
phone. We may therefore at least consider his tele¬ 
phone the successful type, and shall describe its 
evolution without considering it necessary to make 
constant reference to those who had something similar 
in hand or in view. 

Bell was born in Edinburgh in 1847, and is now 
nearly sixty. He studied in Edinburgh and London 


206 TELEPHONE AND ELECTEIC LIGHT 


Universities, and in 1870 went with his father to 
Canada where he was on a farm. In 1873, he became 
Professor of Yocal Physiology in Boston University, 
and in the course of experiments meant to make sound 
visible to deaf-mutes, he came to the conclusion that 
speech might be conveyed by electricity. 

His early apparatus consisted of means for causing 
stretched membranes to move the armatures of mag¬ 
nets, or to move a bit of metal to and fro near the 
pole of a magnet. This set up slight disturbances in 
the magnetic field, and these were repeated in a coil 
attached by a long conductor to another coil around a 
magnet. The second magnet thus affected attracted 
or repelled a bit of iron attached to a second 
membrane, and so repeated the vibrations of the 
first. 

The first results were not wholly satisfactory though 
they seemed to prove the principle correct, but 
despite the protests of friends who believed he would 
do better to give his time to multiple telegraphy, Bell 
persevered, and finally attained success. 

Bell’s patent was granted on March 7, 1876. And 
not many months later he offered the apparatus as an 
exhibit at the Centennial Exhibition in Philadelphia. 
The judges were little impressed, but Dom Pedro, 
the Emperor of Brazil, happening to be present, re¬ 
quested a trial of the instrument, and his commenda¬ 
tion secured a place for the new invention. 

The apparatus exhibited was very simple, and yet it 
had the essentials of the modern telephone-receiver 
— which will act also as a transmitter, though in that 
use it has been bettered. A straight permanent mag¬ 
net is surrounded by a coil of insulated wire. In 


TELEPHONE AND ELECTRIC LIGHT 207 


front of the magnet is a metal diaphragm. Speech 
makes this diaphragm vibrate. As it approaches or 
recedes from the magnet, it induces electric currents 
in the magnet and coil —as vve know from Faradav’s 
experiment, the foundation of all inventions based on 
induced currents. These cur¬ 
rents, conducted to the coil of 
a similar instrument, cause the 
strength of the other magnet to 
vary, set the other diaphragm in 
motion, duplicating the motions 
of the other diaphragm, vibrating 
the air as it was vibrated at the 
other end, and so reproducing the 
sounds. 

Of course these secondary 
motions were feebler than the 
original motions, since there was 
a loss of power all along the line, 
by the friction and resistance of 
the parts, and so on. But the talk 
was repeated, and later inventions 
corrected the faults. 

Three minor advances also be¬ 
long to the Centennial year, type plate. “ B_com P ound 

° J magnet. L—Soft Iron pole- 

One of these is Edison’s electric P iece 
pen — a cylinder like a pencil, in which a point is 
kept in vibration with great rapidity by means of 
electricity acting through magnet coils on a tiny 
circuit breaker. The point made punctures in 
paper as it was moved in writing, and then 
the paper could be used as a stencil. Later de¬ 
vices for copying have superseded this clever device. 



Bell Telephone 

A—Diaphragm of thin ferro- 
















208 TELEPHONE AND ELECTRIC LIGHT 


The second was the increased use of the electric light 
in photography, and the third was also Edison’s — an 
electric meter based on the principle that an electro 
current deposits metal in an electrolytic bath accord¬ 
ing to the amount of current passing through a 
solution — the principle discovered and announced by 
Faraday in his voltameter. Edison’s apparatus was 
simply twin voltameters in a locked box (each being 
used to check the other’s record). When current passes 
through the zinc plates in the solutions of zinc sulphate, 
there is new metallic zinc deposited on the plates, and 



Edison’s Chemical Meter 

This device played an important part in making the 
use of electricity commercially possible. 


the amount thus added is greater or less according to 
the current and the time it lasts. Bv weighing 1 the 
zinc plates, the gain in zinc serves to measure the 
current, being proportional to it. The meter is put on 
a side or shunt circuit, but the relation between the 
main current and the shunt being known, the amount 
of electricity used in a house or factory or by a 
machine or a lighting circuit could be known, 
and, if sold, charged for. To keep the temperature 

















TELEPHONE AND ELECTRIC LIGHT 209 


above freezing, a tiny t amp was put into the box, and 
automatically lighted or put out as necessary by a 
conducting expansion bar that made electric con¬ 
nection with the lamp. 

This was a help to the establishing of companies 
selling electricity. A later meter caused the increase 
of weight in the measuring plate to operate a mechan¬ 
ism. The means employed was a balance, to the ends 
of which the two plates were hung. As one plate in¬ 
creased in weight it overbalances the other, and the 
beam of the balance descended — at the same time re- 
„ versing the direction of the current by moving a 
switch. Then the other plate received the deposit 
until it descended in its turn. As the beam moved it 
recorded its motions on dials by clockwork. This 
was not entirely a new principle, but an adaptation of 
a device used in electro-plating. 

Other meters have used a moving pendulum, kept 
in motion by electricity, or an electro-motor that turns 
a governor like that on a steam engine, and raises the 
governor arms against the pull of an electro magnet 
put below, but these are only ingenious pieces of 
mechanism, using no new electrical principle. 

In 1877 was invented Jablochoff’s electric candle, 
an arc light burning carbons in a new way. Before 
this time complicated mechanism was used to keep the 
carbons at a fixed distance apart so that the arc would 
be maintained. Jablochoff, a Russian officer, was 
clever enough to see that the carbons need not be 
driven tandem in order to come end to end. He put 
his carbon rods side by side, separating them by a strip 
of insulating material that would burn away only just 
by the arc. Once lighted by the passing of the cur- 


210 TELEPHONE AND ELECTRIC LIGHT 


rent, the lamp would burn steadily, destroying the in¬ 
sulation (kaolin — a kind of china-clay) and exposing 
the carbons as required. As to the lighting, this was 
provided for by connecting the tops of the carbons by 
a small strip, that subsequently burns aivay. 

But the two carbons burn unequally. First he made 
the positive, or quick burning carbon, thicker ; but this 
made the resistance of the thinner carbon greater, and 
it burned too quickly. Therefore he simply used the 



The Jablochoff Candle ( 1877 ) 


alternating current and carbons of equal size — causing 
them to be equally consumed. This was very con¬ 
venient, for the ordinarv electric machine then in use 
gave the alternating currents. 

Next the kaolin (which melted at the arc, and when 
melted became an incandescent conductor — using up 
much current in heat) was replaced by a mixture of 
sulphate of lime two parts and sulphate of baryta, one 















TELEPHONE AND ELECTRIC LIGHT 211 


part. This burned to a vapor, and as a gas increases the 
light, and is as easy to make as plaster. 

Though still subject to some faults the light was 
practical and serviceable, being much used. The 
main difficulty was to prevent the cracking of the in¬ 
sulation, for cracks made short circuits, and to keep its 
consuming even with that of the carbons so these 
should have the arc only between the points. 

Each candle burned two hours, and then the current 
could be switched to another. Later this switching 
was done automatically. Usually four were in each 
group — as in the Avenue de L’Opera, Paris, and thus 
burned eight hours. Many improvements in the 
mechanical features were made, and the Jablochoff 
candles found extended use in Europe and to less ex¬ 
tent in America. 


CHAPTER XIX 


SOME USES OF CARBOX 



Another light of the same period is the Sawyer- 
Mann lamp in its earliest form, which used an in¬ 
candescent conductor in a globe of nitrogen gas but 

their improved lamps were 
not patented until 1880. In 
1879 Moses Farmer also 
brought out a carbon lamp 
in an exhausted globe and 
lighted a house at Newport 
with it, but all these lamps 
were soon to be superseded 
by the better form using a 
carbon filament invented bv 
Edison about 1879 and 1880 
and later. 

But earlier than these 
came two improved tele¬ 
phone transmitters — those 
of Berliner and Edison. Ber¬ 
liner fded application for a 
patent in 1877, but as his right 
was contested by Gray, Edi¬ 
son, Bell, and many others, 
it was not granted till 1891. To disentangle the 
claims would require experts and patent lawyers, but 
the credit of the improvement is usually given to 


The Sawyer-Mann Lamp 

A—Incandescent Conductor. 


212 








SOME USES OF CARBON 


213 


Berliner and Edison. The general principle back of 
the invention lay in the discovery that carbon varied 
its electrical resistance enormously under very slight 
pressures. This is due to the French physicist, du 
Moncel, who found that in the contact of two con¬ 
ductors the resistance is proportionate to the lack of 
pressure ; and also to Professor Hughes of England, in¬ 
ventor of the printing telegraph and of the microphone 
in 1878. He discovered in a course of experiments that 
when substances of high resistance were in a circuit in 
loose contact their conductivity became much increased 
by even the slight pressures such as were caused by 
vibrations. On this principle he made his microphone. 
Fixing two carbon blocks in a support made of a 
block of wood he set upright between them a double 
pointed stick of carbon, the points resting in little 
holes in the other carbons. To the supports were at¬ 
tached wires leading to a telephone receiver, and the 
battery—all three being in the circuit. Now even 
the smallest sound vibrations are found to change the 
resistance of the carbon very greatly, to cause magni¬ 
fied vibrations of the diaphragm in the telephone, and 
so to be heard as if through a magnifier of sound. 
Just as microscope means a viewer of small objects a 
microphone means a hearer of small sounds, and even 
a fly’s footsteps could be made plainly audible by a 
proper apparatus. 

Both Berliner and Edison, as well as Hughes and 
others, promptly set to work to combine the induction 
coil and the microphone feature with the telephone- 
transmitter— where the sound-magnifying power was 
sorely needed. It should be mentioned here, as Pro¬ 
fessor Houston suggests, that the first telephone- 


214 


SOME USES OF CARBON 


receiver — Reis’s — was really a form of microphone 
instrument. 

But we cannot go into the history of the various 
inventions that made up the receiver finally adopted, 
nor can we show how the microphone itself was in¬ 
creased in power and in its applications by multiplying 
the rods of carbon and other means. About 1880 the 
increase in electric inventions and applications and 
combinations of known methods to new purposes was 
so enormous that we must resolutely confine ourselves 



Hughes’ Microphone 

In this instrument, a rod of carbon, pointed at both ends is 
loosely held in two small holes in blocks of carbon at each end, 
supported on a wooden sounding-board. These blocks are 
connected in circuit with a voltaic battery and if a telephone 
receiver is then placed in the circuit, talking or singing can 
be plainly heard through it. 

to the main steps of advance, leaving to technical stu¬ 
dents the study of special departments. 

But the new telephone-transmitters were of vast 
importance, and in order to show what they were we 
shall give a few moments to the commercial forms of 
these instruments — mentioning, however, that there 
are numerous other effective forms. 

The Blake transmitter is a mechanical adaptation of 
the principles of Hughes’s microphone and of the in¬ 
duction coil as applied to the telephone by Berliner 

















SOME USES OF CABBON 


215 


and of the carbon-button transmitter invented by 
Edison, and is still in use. It is the apparatus con¬ 
tained in the familiar box of the telephone that is 
fastened to the wall. Opening the door one finds it 
to carry a diaphragm in a circular iron frame, and 
this diaphragm is supported on one edge but free to 
move and vibrate. In front of it is a microphone, con- 



The Blake Transmitter 

A—Cast iron ring. B D—Diaphragm. C—Casting to support diaphragm. 

E—Spring through which connection is made, a b—Binding posts for battery 
terminals, c d—Binding posts for line terminals. 

nected by means of a platinum rod on a spring, which 
rod touches diaphragm and microphone. Inside the 
box rests an induction coil. 

The primary wire of the induction coil *; connected 
with the transmitter, the secondary wire with the line. 
We speak into the mouthpiece, its diaphragm vi- 














































































































































216 


SOME USES OF CARBON 


brates, and sends induced currents through the micro¬ 
phone and the primary wire of the induction coil. 
The induction coil then sends the impulses through 
the line to the other telephone-receiver, being aided 
by a heavier charge afforded by a battery. This 
battery though it operates the induction coil does not 
prevent the currents from being modified by those 
sent through the microphone. 

If the reader will carefully consider the telephone 
from beginning to end, he will see that the apparatus 
combines in one apparatus the discoveries and inven¬ 
tions of dozens of investigators of whom we have 
spoken — from the Faraday induction coil (to go no 
further back) to Professor Hughes’s microphone. By 
1878 the first telephone exchange was in operation, 
the first long line — Salem to Boston — having been 
built the year before. That was long for those days, 
but the growth has been so rapid that it seems a tri¬ 
fling distance indeed. 

About 1878 also Edison introduced his carbon-fila¬ 
ment lamp, having to meet an interference claim in 
the Patent Office with Sawyer and Mann who also 
claimed the invention. But the courts in 1892 
awarded the invention to Edison. He had begun to 
study the problem in the thorough way that has made 
him so successful, on his own principle that inventive 
genius is “ one-third inspiration, two-thirds perspira¬ 
tion.” He cleared his laboratory of all the telephone 
and phonograph materials, and set to work to solve 
the problem of practicable electric lighting. He 
turned from the arc light because it was not possible 
to make it steady, and studied the incandescent light. 
He found it needed an incandescent substance that 


SOME USES OF CAEBON 


217 


would be cheap, lasting, offer the right resistance, and 
be ductile enough to form fine wire-like filaments. 
Another most important need for the filament was 
that it should be “ refractory ” — that is, be able to be 
heated to a very high degree for a long time without 
being destroyed or fused. He tried platinum and 
other rarer metals, and made successful lamps with 
platinum filaments; but it was not satisfactory. 

Edison then experimented upon various forms of car¬ 
bon, and made the carbon from all sorts of fibres, and 
at last resolved to try natural wood fibres, charred to 
carbon. He sent men all through the world, collected 
fibres and tested them patiently, at last choosing bam¬ 
boo. Then the different kinds of this wood were tried 
in the same exhaustive manner and a certain Japanese 
bamboo selected as the best. But this was a little 
later than the period we have reached. 

In 1879 the first actual electric railway run from a 



Siemens’s First Electric Railway, Berlin, 1879 


central station was established in Berlin, but only for 
showing the principle at the Industrial Exhibition. It 
was a circular track about 1,000 feet long, and the 
dynamo supplied about five horse-power. This rail¬ 
way had been designed by Dr. Werner Siemens at the 
request of a mining company. It carried thousands 














218 


SOME USES OF CARBON 


of people daring the exhibition. Next in order came 
Edison’s dynamo .railway at Menlo Park, in 1881. 
Both the Siemens and the Edison railways were run 
by electric current transmitted by a rail, the Siemens 
railway taking power from a third rail between the 
others. But the patent office granted to Stephen D. 
Field in 1891 a patent, based on a caveat liled in 
1879, for operating a railway by a current conducted 
through the rails to a motor. The Field and Edison 
interests had earlier joined forces, and in 1881 and 
1883 railways on their designs were run in Stockbridge 
and in Chicago at a Railway Exposition. The current 
furnished by a shunt-wound dynamo followed a central 
third rail, operated a motor on the same plan as the 
dynamo, and then returned to the station by the other 
rails. But there were no commercial street railways 
in operation until 1885. 

Meanwhile in 1882 and 1883 other inventors had 
used a suspended wire for bringing the current from 
the central station to the motor, and the cheapness 
and handiness of this system (introduced by Dr. J. R. 
Finney of Pennsylvania), was to give it an enormous 
advantage, though Finney’s trolley-wheel was con¬ 
nected to the motor through a flexible cord, and is 
said to have worked well only at moderate speeds ; 
but this was the forerunner of the pole-trolley that 
has seemed to solve the problem of cheap electric 
roads for local traffic and suburban lines. 

It was just after 1881, the year of the first general 
Electric Congress in Paris that the electrical standard 
units began to come into use all over the world. The 
system is based on the metric system, and is built up 
out of the metrical units the centimetre, the gramme, 


SOME USES OF CARBON 


219 


and the second (of time). Hence it is called by the 
initials of these words — the “ C. G. S. System.” The 
shortest statement of the system is by means of a 
table. These are the C. G. S. units: 1 

The Unit of Force=propels one Gramme one 
Centimetre in one Second=l dyne. 

Work unit—1 dyne X 1 centimetre=l erg. 

Quantity unit=quantity conveyed by 1 dyne in one 
second (=10 coulombs). But these are inconveniently 
small for practical work, and therefore they have been 
replaced by practical units derived from them, as 
follows : 

The ampere=-TT> the current strength unit in the 
C. G. S. system. 

The volt= 100,000,000 (sometimes written 10 8 mean¬ 
ing 1 and 8 ciphers) C. G. S. units, is the unit of elec¬ 
tro motive force. 

The ohm —the resistance of a conductor that 
will produce one ampere from one volt=10 9 (or 
1,000,000,000 C. G. S. units). 

The coulomb=the quantity carried by unit current, 
one ampere in one second. 

Philip Atkinson in “Electricity for Everybody” 
gives comparisons by which the general reader may 
get some definite idea of these practical units — the 
only ones he is likely to meet with except in special 
investigation. The volt, he explains, is very nearly 
(.926) the electric pressure of one Daniell battery cell; 
and it must be remembered that the pressure is the 

1 For a full table, see “Standard Dictionary” under “unit.” An 
excellent statement and explanation of these units will also be found 
in “The Story of Electricity,” by John Munro, published by Mac¬ 
millan & Co, 


220 


SOME USES OF CAEBON 


same whatever the size. The ohm is about the resist¬ 
ance of an ordinary thermometer column of quick¬ 
silver increased to nearly 41^ inches in length at 32° 
Fahrenheit temperature— freezing point. Or, we may 
quote from Professor Houston, it is equal to the resist¬ 
ance of one foot thin (40 American gauge) copper 
wire, or two miles of ordinary trolley wire — as we 
have before said. And the ampere is the current a 
Daniell cell would send through such a column. A 
coulomb would be the amount of electricity flowing 
along such a column from the Daniell cell in one second. 

For the sake of completeness the following units are 

added from Alglave and Poulard’s “ The Electric 

Light.” They are merely defined, not fully explained, 

as thev are found in modern dictionaries: 

«/ 

Farad (from “ Faraday ”) is the unit of capacity= 
nnnnnnnnnr C. G. S. unit of capacity. The Microfarad is 
one millionth of a Farad. 

Calorie (from “ Caloric ”), unit of A^^=4.2X10,- 
000,000 ergs. 

Joule (from the name), unit of worh=\0 i 000,000 ergs. 

Watt (from the name), unit of 10,000,000 

ergs a second. 

746 Watts=one (English) horse-power. 

735.75 Watts=one (French) force de cheval. 1 


1 One centimetre=.3937 inch. 

One gramme=15.432 grains=l fifth the weight of afive-cent nickel. 
Hence to move a nickel £ of an inch requires 5 dynes, against no re¬ 
sistance. To lift it is to act against gravity, which is about 981 dynes 
(since it moves a falling nickel with an increased velocity every 
second sufficient to carry it through 981 centimetres). Therefore 5 
(grammes)X981(dynes)=the number of Ergs done in lifting a nickel 
a little over a third of an inch, or 4,905 Ergs. A Watt ( 7 H horse¬ 
power) is equal to 10,000,000 Ergs, 


SOME USES OF CARBON 


221 


To give another simple table, derived from the re¬ 
lation of the commoner units: 

E. M. F.=Volt=AmpereXOhm. 

Resistance=Ohm=Volt-7- Ampere. 

Current=Ampere=Volt-j-Ohm. 

Quan tity=Coulomb=AmpereXsecond. 

Capacity=Farad=Coulomb-i-Volt. 

The farad is the capacity of a conductor capable of 
holding one coulomb at one volt potential. 

AVork=Watt—VoltXAmpere=Ti6 horse-power, or 
44.25 foot-pounds a minute. 

Kilo watt=l,000 watts—nearly 1% horse-power. 

The prefix Kilo is used in the same way to multiply 
other quantities, as Kilerg=l,000 ergs ; Kilo-ampere ; 
and so on. Other units exist and find special use, but 
all are derived from some of those mentioned above. 
In practical handbooks tables are given showing the 
electrical qualities of wire and so on. Thus we find 
that wire of pure copper about 2y£ millimeters in 
diameter (2.588) gives one ohm resistance when 1,000 
feet long, and may be safely used with current of 
about 20-40 amperes, depending on whether it is in 
open or u concealed ” work ; and that hard drawn cop¬ 
per wire guage No. 10, B. & S., weighs 104 pounds to 
the mile and offers 8.7 Ohms resistance per mile. 
These figures are taken from a pocket “ Compend of 
Electricity,” by J. A. Beaton, published in Chicago in 
1901. 

Enough —perhaps more than enough — has been said 
to show how the science of electricity has created a 
new set of words for the languages of the world, 
though fortunately by international comity, these 
words are alike in all languages. One might fancy 


222 


SOME USES OF CARBON 


electricians to converse in them to a certain extent, 
though ignorant of each other’s native tongues. Thus 
one might point to a high hill and write on a pad, 
“ 100,000 Ohms ! ” to indicate it would be difficult to 
climb, while the other might reply by pointing to his 
sturdy legs as capable of a “ Kilowatt.” 

But, seriously, it is of enormous value to the world’s 
progress that scientists should be able to make their 
work easily intelligible to the whole world by a com¬ 
mon system of units, and these also carry with them 
similar names for electrical instruments and similar 
diagrams and symbols to explain the action of elec¬ 
trical apparatus. 


CHAPTER XX 


ELECTRICITY APPLIED IX ALL FIELDS 

In order to proceed to the year 1885 only a few 
items of progress need be mentioned. An experimen¬ 
tal telephone line was built from New York to Boston, 
and proved so successful that within three years it was 
equipped and opened to the public. 

A second congress of electricians was held in Paris 
in 1884, confirmed the standard units, and adopted the 
Farad, possibly at the suggestion of Sir Werner 
Siemens who named the “Watt.” There was added 
to the methods of conveying current to a railway 
motor the use of an underground system, in which the 
conductor of the current was in a conduit. Thus in 
1883 there was more than a beginning of practical 
electric railways, for Leo Daft of New Jersey had 
operated a small railroad between Saratoga and 
Mount McGregor two years before that; and in 1885 
there was a suburban line two miles long from Balti¬ 
more to Hampden, also designed and constructed by 
the same electrician. In the year 1886 the railway 
operated on the system of Charles J. VanDepoele was 
opened in Scranton, Pennsylvania, and by 1888 there 
were “ twenty-three lines having a total length of 
about a hundred miles,” says Franklin L. Pope in 
“ Electricity in Daily Life.” 

Between 1885 and 1890 there was similar progress 
in other electrical industries. Elihu Thompson made 

223 


224 ELECTRICITY APPLIED IN ALL FIELDS 


use of the intense heat of the electric-arc for welding 
metals, his earliest patent being dated August 10, 
1886. He used a current of small voltage but high 
amperage, and by a number of inventions adapted his 
process to all kinds of work, using transformers to 
control the current, clamps to fasten the work together 
until welded, and so on. The process is complicated, 
but contains no really new electrical principle, being 
merely a combination of ingenious methods of apply¬ 
ing the current in the right condition and shutting it 
off when the work is done. The process succeeds 
readily with metals that do not weld in ordinary 
methods, and can be applied — as in welding together 
the already laid rails of a railway — almost anywhere. 

Here again is a whole new art that would require a 
volume if not a library to itself, for it includes electric 
welding, forging, casting, and soldering. As has been 
well said in “ Flame, Electricity and the Camera,” the 
control of the electric current has not added to man’s 
powers so much as multiplied them. “As we trace a 
few of the unending interlacements of electrical sci¬ 
ence and art with other sciences and arts,” says the 
author, George lies, “ and study their mutually stimu¬ 
lating effects, we shall be reminded of a series of 
permutations, where the latest of the factors, because 
latest, multiplies all prior factors in an unexampled 
degree. . . . This principle stands forth in that 

latest accession to skill and interpretation which has 
been ushered forth by Franklin and Yolta, Faraday 
and Henry.” 

So, as it is impossible to write the history of all arts 
at once, we cannot tell how al] of them have been re¬ 
created by the power to carry electricity to any work 


ELECTRICITY APPLIED IN ALL FIELDS 225 


and then to cause it to do work in the form most con¬ 
venient— whether as electric vibration, chemical 
action, heat, power or light; whether as tool, de¬ 
tector, regulator, or destroyer. 

We have given somewhat full explanations of the 
earlier electric inventions, especially of such as enable 
the reader to understand the principles that underlie 
later applications. But the increasing complexity and 
broadened field of modern electricity is multiplied in 
geometrical ratio. Each invention gives rise to dozens 
more, and we are therefore compelled by our limited 
space and by our purpose, to pass by with only a hint 
as to their method of working countless minor de¬ 
vices by which inventors have brought electricity into 
use to serve mankind. 

Still we believe that with an understanding of the 
principles already explained herein, the reader will be 
able to see the general idea of modern electric devices, 
and by careful examination of the current path, as the 
electro motive force traverses its conductors, coils, 
and magnets, and is changed to light, heat, or me¬ 
chanical motion, to see why the effects are produced. 

In the early days a few popular lectures would put 
any one in possession of the essential facts known 
about electricity. Now the training of an electrician 
requires not only a liberal education from the begin¬ 
ning, but daily study to keep up with the progress of 
each specialty. A prominent electrician is said to 
have remarked recently that if he simply kept himself 
informed as to the constant additions to his science, he 
could find time for nothing else. Besides, it is not 
necessary to carry in one’s head a great mass of facts 
that are instantly available through reference-books 


226 ELECTRICITY APPLIED IN ALL FIELDS 


whenever needed. H. G. Wells remarks with equal 
wisdom and wit that most facts “ keep better in the 
books than in the brain.” The specialist will have his 
own library, the occasional student may consult the 
public libraries, and every one should have at hand at 
least the small hand-books that can be bought for 
half a dollar or less. These will be available at any 
moment, and in general they are very good and very 
helpful in understanding such electrical terms and 
phrases, or such new inventions as are part of the 
news of the day. 

After reading even so general a little book as this 
is, no one will be so foolish as to look upon electricity 
as a magical creation of power. Like all the forces 
with which man deals, electricity must be paid for 
either in work or in ingenuity of application and con¬ 
trol. If we make a dynamo to run a motor, we must 
supply energy to the dynamo by steam, wind, water, 
or chemical power. Even a waterfall, power in a 
most usable form, must be harnessed and directed in 
order to change its motion into that rotary form we 
find most useful; and as yet there is no way of arriv¬ 
ing directly at any great reservoir of steady electrical 
energy. That may some day be found in the light 
waves that come from the sun, and on Clerk Maxwell’s 
theory that light and electric waves are different 
manifestations of the same energy, the taking of elec¬ 
tricity directly from sunlight may be 'looked upon as 
possible. But meanwhile electricity is used as a form 
of power, and the power must be taken from natural 
forces before it can be electrically applied. 

An interesting story of the great philosopher 
Faraday illustrates not only his wisdom but his com- 


ELECTRICITY APPLIED IK ALL FIELDS 227 


mon sense. It is said that an inventor exhibited an 
electric machine to a number of capitalists and ex¬ 
perts, including Faraday, and made great claims as to 
its commercial value. Then he started it, and caused 
a large fly-wheel to revolve rapidly while his specta¬ 
tors gazed. Faraday picked up a broom, and pressed 
the handle against the edge of the wheel. The wheel 
slowed down, “ hesitated,” and came to rest. Fara¬ 
day left the room in silence, and very likely the 
capitalists followed. 

He knew that electricity did not create power, and 
in those days of voltaic cells, the electric machine was 
not what it has since become. 

But it has been truly objected by a thoughtful critic 
that Faraday did not at all appreciate the wonderful 
possibilities in the device he was viewing. He — great 
genius as he was — did not see that a change in cer¬ 
tain conditions was to make the electric motor a 
commercial possibility. 

To return to our story, the year 1887 was notable 
not only for practical progress but for advances in 
theoretical study that were the foundation of great 
improvements later. The telephone was rapidly being 
extended as its instruments were improved and as the 
public became educated in its convenience; and the 
electric motors and electric light were also firmly es¬ 
tablished as every-day matters. But a new name is 
met with, in the electrical field, in connection with the 
theory of dynamos and motors,' and of electric wave- 
motion — that of Nikola Tesla. In 1882 he made an 
invention which has become known as a “rotating 
magnetic field,” but Professor Houston declares that 
some portion of the credit must (as usual) be ascribed 


228 ELECTRICITY APPLIED IN ALL FIELDS 


to other workers in the same field — of whom he 
names especially Professor Galileo Ferraris. Yet to 
Tesla the chief credit undoubtedly belongs. He was 
born in 1857, a Serbian, educated abroad, and becom¬ 
ing an engineer and inventor worked for some time 
in the Edison laboratory, lie subsequently established 
a laboratory of his own, and became the Electrician 
of the Tesla Electric Light Company of New York. 

His inventions relate to electric lighting, power, and 
transformation ; but the most important of all is a 
form of electric dynamo and motor known as the 
multiphase or polyphase. It has neither commutator 
nor brushes. Though ridiculed when he proposed to 
eliminate these, by 18S8 he had made multiphase 
motors equal to any of the old types in efficiency. 
These motors have later been called “ induction 
motors,” since they operate b} 7 inducing currents from 
the field, or “ stator,” in the armature ring, or “ rotor.” 

Consider a ring-armature wound with a closed spiral 
coil of wire all in the same direction. Now let two 
alternating currents be supplied and withdrawn at 
four equi-distant points — say, North and South, 
East and West — so that when one is at its highest 
potency the other is at its lowest. That is, one enters 
at N, leaves at S ; the other enters at E, leaves at W. 
Imagine the ring fixed, and a magnetic needle placed 
in the centre, and free to rotate. Then as the first 
current enters at N, the needle is moved to turn 
across it; but this current is now losing power, and 
the next current influences the needle to turn further 
round to cross that current (by Oersted’s deflection 
principle). It moves still more, and is thus brought 
into the influence of the first current 1 'eversed , turns, 


ELECTRICITY APPLIED IN ALL FIELDS 229 


and comes within the field of the second current re¬ 
versed and so on. 

In short, all around the circle, the current is supplied 
in such direction and force as will keep the needle 
turning in one direction. This will be easy to under¬ 
stand if we suppose four electricians to be standing at 
the four quarters of the ring with positive and nega¬ 
tive live wires, and at each quarter to apply the right 
current to keep the needle deflecting in one direction 
— that is revolving. But what the electricians could 
do by hand is done with enormous speed mechanically 
by the motor-mechanism. So the needle keeps on 
turning. 

It is therefore a motor. But in the actual machine 
instead of a needle, another ring free to revolve is 
put inside the first or “ stator ” ring. And this second 
or “ rotor ” ring is so wound with a number of closed 
coils of wire that when electrified by induction cur¬ 
rents it revolves as the magnet would — but at 
enormous speed. 

Such is the polyphase motor with two currents, 
called the diphase motor. But the same principle can 
be applied to smaller parts of the stator ring than a 
quarter, and so we have the triphase or multiphase 
motors — in which currents enter the ring at many 
points but always in the direction that will keep the 
rotor ring turning. 

It will be seen that, given the wires conducting the 
necessary currents, only two parts are necessary in 
these motors and dynamos — the rotor ring, and the 
stator ring, each properly wound. In fact it seems as 
if simplicity could go no further — unless we should 
be able to make electric fields without any conductors 


230 ELECTRICITY APPLIED IN ALL FIELDS 


at all — simply currents whirling in the ether ! And 
these motors can be placed anywhere that a pulley of 
the same size would go — at the top of a pole, against 
a ceiling or wall, or in a pit. Used as dynamos to 
give electric current, they may be placed On a shaft, 
like any wheel — and are thus especially fitted to be 
used with the turbine water-wheel, as at Niagara. 

They do need, however, a starter when of large 



c d 

The Polyphase Induction Motor (Westinghouse Type). 

A —The housing and primary, or stator unwound. B—The primary, or 
stator complete. C—Core of secondary, or rotor unwound. D—The sec¬ 
ondary, or rotor, complete. 

size; but this means only the momentary putting of a 
transformer in the circuit by means of a switch, that 
will supply a smaller voltage for a while. The reason 
they need to be started will be evident on reflecting 
that the currents are applied successively, and if all 
were turned on at once, the moment lost in overcom¬ 
ing the rotor’s inertia would cause simultaneous in¬ 
stead of successive action of the currents for that 













































ELECTRICITY APPLIED IR ALL FIELDS 231 


moment. It would be like a steam engine when on 
a “ dead centre.” 

The polyphase machines have no brushes to waste 
power in sparks, no commutators to be injured, no 
connections where arcs can be formed to heat or burn 
the apparatus. They are almost ideal machines, need¬ 
ing only a ready means of regulating their speed. 
And this has already been furnished in more or less 
perfect form, by devices for regulating the currents 
supplied to them. 

Of course the direct current motors, the alternating 
current motors, and the polyphase motors will each 
eventually find the use for which it is best adopted. 
For it is universally true that very few machines are 
entirely superseded by later inventions, being only re¬ 
placed for particular uses. 

It will be remembered that in 1815 Faraday had 
observed that polarized light was affected by mag¬ 
netism— that the rays were turned about an axis, or 
rotated, by a magnet. Twenty years later the con¬ 
nection between light and magnetism or electricity 
was expressly asserted by Clerk Maxwell, who found 
that the speed of light waves and that of electric 
waves were the same. 

Twenty-two years later, in 1887, another proof 
was found that the light energy and electric energy 
were identical or closely connected. By means of a 
device for enormously .increasing the reversings of an 
electric current, the investigator Hertz produced cer¬ 
tain waves in the ether which, though caused by elec¬ 
tricity, could be reflected by a mirror, could be sep¬ 
arated into their simple waves (or their elements, 
much as light is separated by a prism) and would even 


232 ELECTRICITY APPLIED IN ALL FIELDS 


cast shadows. As Mr. Bowker says in his article, 
“Electricity,” published in Harper's Magazine, “In 
short, though produced by electricity, they acted like 
light; which seemed to confirm by experiment the 
theory of Maxwell.” 

Heinrich Hertz was born in 1857 at Hamburg, and 
became a professor at Karlsruhe and afterward at 
Bonn, where he died in 1894. Though he is credited 
with the discovery of the identity of light and electric 
waves, it should rather be said that by experiment he 
furnished the proof that certain electric waves could 
be made to follow the same laws as light waves. It 
will be remembered also that in speaking of Professor 
Henry’s discoveries we noted that he discovered the 
discharge from a Leyden jar to be an oscillation, or a 
to and fro movement in opposite directions of the 
ether. Clerk Maxwell had shown that if these oscil¬ 
lations could be produced at certain given rates these 
waves could be made to act like the waves of light, 
sound and heat. 

As stated by Sir Oliver Lodge, Maxwell’s dis¬ 
coveries amounted to a proof, or almost a proof, that 
light is in fact an electro-magnetic disturbance. There 
are to-day so many proofs that the two forms of 
energy are identical that we may even assert the fact 
and add that every day brings new evidence to com¬ 
plete the proof. 

We shall not attempt to go very deeply into the 
question of ether waves. We must take for granted 
the conclusions of the greatest experimenters that 
there exists throughout space and extending through¬ 
out the substance of all kinds of matter something 
known as the “ether,” which is described as a medium 


ELECTRICITY APPLIED IN ALL FIELDS 233 


without weight infinitely, more subtle than air, capable 
of receiving and transmitting vibrations at different 
rates. These vibrations, known as ether waves, vary 
in direction of vibration, in speed, and in extent. 
According to their extent, their speed and their direc¬ 
tion, they produce effects which give rise to what we 
know as heat, light, electricity and magnetism. They 
are also produced by all forms of mechanical action, 
and in fact are believed to be caused by every form of 
motion and every manifestation of energy. 

Sir Oliver Lodge in England a few years before 
Hertz’s experiments began had discovered that by 
rapidly charging and discharging a Leyden jar in the 
neighborhood of another similar jar, but without any 
conductor between them, he was able to charge the 
second jar electrically. But this effect was produced 
only between jars that were so far alike as to be con¬ 
sidered in electrical tune with one another. In order 
to bring them to the same electrical harmony, Lodge 
devised a method of changing the dimensions of the 
second until it responded to the first, just as in a 
musical instrument a string may be tuned so as to re¬ 
spond to another. 

A very similar method of procedure was adopted 
by Llertz, who devised an effective apparatus for set¬ 
ting up and for receiving oscillations. Before describ¬ 
ing the nature of his devices it will be well to see just 
what place in the art of electricity they occupy by 
making a sort of tabulation showing the general 
progress in knowledge of electricity. 

The first discovery made by man was that certain 
bodies were in a state known as electrified, that is, 
they were in a state that would under proper condi- 


234 ELECTRICITY APPLIED IN ALL FIELDS 


tions attract or repel certain substances. This state 
was that of electricity at rest, or static electricity. 
Next it was found that by means of supplying paths 
or conductors the electrical energy could be conveyed 
along the conductors to other things. This was elec¬ 
tricity moving, or “ current ” electricity. The third 
step was to detect in magnets electricity constantly 
moving in a circular path, or “ rotating ” electricity. 
Man learned to understand, and then to produce at 
will, and to some extent to govern, these three states. 

The next step was the discovery of still a fourth 
state where electricity, or the ether wave-motion, was 
in vibration or radiation ; that is to say, the disturb¬ 
ances in the ether appeared in the form of to-and-fro 
motion and were transmitted through space without 
any conductor. 

This classification of the gradual steps of electrical 
science is quoted from Sir Oliver Lodge by Charles R. 
Gibson in his “ Romance of Electricity,” and will en¬ 
able us to understand the great importance of the step 
forward made by Faraday’s discovery of the electric 
action on light waves, by Maxwell’s wonderful theory 
of their action and their identity with light waves, 
and Lodge’s and Heinrich Hertz’s invention of prac¬ 
tical means for producing electric waves, or electricity 
in this fourth state. 

Hertz’s apparatus consisted of a large induction 
coil prepared so as to produce sparks ; that is, the ends 
of the secondary coil, or that in which the current is 
induced, were connected to brass balls or knobs mov¬ 
able so as to be placed at different distances from one 
another. These knobs can be adjusted at just the 
right distances apart so that the induced current is 


ELECTRICITY APPLIED IN ALL FIELDS 235 


strong enough to send a spark across from one to the 
other, that is, to overcome the resistance of the air 
gap between them. 

An induction coil and a Leyden jar, as has been 
said, are electrically similar contrivances, and the dis¬ 
charge from a coil, like that from a jar, is an oscilla 
tion setting up waves in the ether, as Henry discov¬ 
ered in 1842. It was Hertz’s theory that these waves, 
if they could be made to strike upon a conductor of 
the right sort, should set up waves around it. He 



bent a copper wire into a circle of about sixteen inches 
diameter, but instead of joining the ends put two 
copper balls on them, so that if the current, or suc¬ 
cession of waves, were to pass along the wire it might be 
visible as a spark when it jumped from one ball to the 
other. This he named the “ electric eye ” or “ de¬ 
tector.” The reader will remember that the object of 
these round balls is to prevent the soundless discharge 
that occurs from points, (as discovered by Franklin), 





236 ELECTEICITY APPLIED IN ALL FIELDS 


and by causing a spark to make the electric action 
visible in light. 

When the induction coil was excited so as to pro¬ 
duce sparks, this wire was held a few feet away by 
means of an insulated handle. The first experiment 
produced sparks in the air cap at the ends of the ring, 
but these were so minute that they could be observed 
only in a darkened room. 

The distance at which this Hertz detector acted was 
not more than a dozen feet, and yet in this experiment 
lay the principle that has created wireless telegraphy. 

The next step necessary to make Hertz’s apparatus 
practically useful was to apply a discovery that has al¬ 
ready been noted, namely, the fact that iron filings, 
although they act as a very poor conductor when in a 
state of loose contact, joined one another (because 
magnetized) to some extent as soon as they were 
brought under electrical influence, and thereby formed 
a conducting path. 

It will be remembered that Morse, in order to ex¬ 
tend the action of his telegraph, invented the relay in 
which he used a weak current to move a small bar 
that closed the circuit of a stronger current. The 
same idea was applied by Professor Branly to causing 
weak Hertizan waves to set in action a strong current. 
He had only to fill a small glass tube with iron filings, 
not packed closely, and to place this tube by means of 
a wire at each end in an electric circuit. 

The discovery of the coherer, as this tube of iron 
filings was called, was the result of a number of re¬ 
searches and experiments beginning as far back as 
1850/ These experiments had shown that the passing 
of an electric spark between two conductors placed 


ELECTRICITY APPLIED IK ALL FIELDS 237 


closely together seemed to make a sort of permanent 
bridge between them. This was studied at first in re¬ 
lation to certain devices known as lightning arrest¬ 
ers, which consist of a gap left in an electric circuit 
wide enough not to be passed over by the ordinary 
charge but not too wide to be crossed when a strong 
current such as a lightning stroke enters the circuit. 

Sir Oliver Lodge, in 1889, modified the usual form 
of lightning arrester — which was two saw-tooth edged 
plates opposite one another but not touching — replac¬ 
ing them with two metal balls. He observed that the 
spark having once passed between these balls, which 
must have been almost in contact, the current con¬ 
tinued to pass from one to the other. These devices 
for detecting electric waves were used for some time 
before they were adapted to the sending of signals, 
and the Branly coherer seems to have been employed 
mainly for detecting electric waves, whether given by 
an apparatus or existing in the air. But the commer¬ 
cial use of the Hertzian waves in telegraphy was not 
to come until after some vears. 

We shall obtain an excellent idea of the extent to 
which electricity had entered the commercial world by 
examining some of the statistics given to show elec¬ 
trical progress by The World Almanac for 1891. The 
amount of money invested in electrical industries in 
the United States at the end of 1890 was computed to 
be six hundred millions of dollars, one-fifth of this in 
telegraphy ; eighty millions, more than one-eighth, in 
telephones, fully one-half, or three hundred millions, in 
electric-light and power companies, and the rest in 
electrical supply companies. Of electric roads there 
were a hundred and thirteen in operation, forty-five 


238 ELECTRICITY APPLIED IN ALL FIELDS 


more being constructed. The subscribers to telephone 
exchanges numbered one hundred and eighty-five 
thousand, using over four hundred million connections 
a year. The number of incandescent lights was over 
eight hundred thousand, and of arc-lights over twenty- 
five thousand. 

Conversation by telephone was carried on over a 
distance of seven hundred and fifty miles ; the fastest 
time made by electric railways was a mile a minute, 
twenty miles an hour was a usual speed in street rail¬ 
ways. The most powerful motor then in use was of 
seventy-five horse-power. 

The novelty of that day, though it had been in use 
for a year or two on one railway, was telegraphing 
from a moving train. This apparent marvel was ac¬ 
complished without great difficulty by the use of an 
induced current. The means of procedure had been 
first suggested as far back as 1853, but did not come 
into practical use until about 1887. The method of 
telegraphing is as follows : Inside any car is carried an 
induction coil that can be thrown into vibration by a 
make-and-break contact, like the Ruhmkorff coil. 
When this is acting it induces a current in its second¬ 
ary coil. This current is connected to the tin roof 
of the car, which also is thus electrified by an alter- 
nating current, first positive, then negative. The 
making and breaking and change in force in this cur¬ 
rent cause an induced current to be set up in a con¬ 
ducting wire stretched above and parallel to the track, 
but of course not in contact with the car. A tele¬ 
graph key of the ordinary sort is now used to start or 
stop the induction coil in the car. When it is closed 
the alternating currents are produced, and when open 


ELECTRICITY APPLIED IN ALL FIELDS 239 


they cease. A long closing of the key makes a dash, 
a short closing a dot, an opening of the key makes a 
space, and a receiving instrument of the ordinary kind 
being connected at any station with the wire beside the 
track can receive signals precisely as if it were in an 
ordinary telegraph circuit. A telephone receiver is, 



Diagram Showing Method of Telegraphing by In¬ 
duction from Moving Train 

In receiving messages electric impulses from the vibrator of an induction 
coil induce currents through the car roof, by wire a, key K, telephone wires 
b c, car wheel and ground. In sending messages closing key K works in¬ 
duction coil I, and vibrator V, through battery B, and primary circuit d e 
f g, and the secondary circuit a h i, charging the metallic car roof, influences 
by induction the line wire and telephone at receiving point. 

however, used as more convenient, and the signals re¬ 
ceived by hearing, ordinarily. 

The transmitting of signals to the car is only a 
reversal of this process, the induction coil in the station 
being connected with the wire stretched parallel to the 
railway lines. Currents set up in this wire induce the 
currents in the car roof, thereby affecting a telephone- 

































240 ELECTRICITY APPLIED IN ALL FIELDS 


receiver attached to the roof by a wire and used in 
the car as before. 

It will be seen that for a short distance this is really 
a form of wireless telegraphy, since the waves be¬ 
tween car and line go through space without a con¬ 
ductor. 

The foregoing description has been based upon an 
article in Scribner's Magazine for 18S9, and the con¬ 
cluding paragraphs of this article plainly foreshadow 
the possible extension of wireless telegraphy to some¬ 
thing like the system we know to-day, though the 
author, Charles M. Buckingham, seems at that time to 
have thought about half a mile the limit within which 
such communication was then possible. It is true, 
however, that he speaks of certain earlier experiments 
wherein parallel wires were used to induce currents 
in one another, as permitting communication for a 
distance of from one and a quarter to six miles, from 
the Isle of Wight to the English coast in Hampshire. 

It will be seen that the missing element in extend¬ 
ing the operation of this system was the relay, namely, 
some device that would detect faint electric waves and 
use them to set in action a stronger current. This was 
to be supplied, as we know, a few years later. 

Also, from The World Almanac of that year, we 
learn that there were about nine hundred and fifty 
submarine cables then in use, covering a distance of 
about a hundred and eighty thousand miles. 

In 1890 the most important events were the general 
adoption of electric light in a number of great foreign 
cities, notably in Rome, Paris, Milan, Tours and 
Marseilles, and the beginning at Niagara Falls of the 
work destined to convert the energy afforded by that 


ELECTRICITY APPLIED IN ALL FIELDS 241 


cataract into electric currents for transmission to a 
distance. 

The progress in electric railways continued in in¬ 
creasing ratio. The earlier motors had been most un¬ 
certain in their operation, not economical nor partic¬ 
ularly well adapted to car-traction. The causes of 
failure were various, but among them may be men¬ 
tioned the burning out of the copper brushes used 
upon the armatures, causing a very great expense for 
their continual replacement, the uncertainty of the 
methods of control adopted for regulating the high 
power transmitted to the motors, and, generally, the 
inferior nature of the motors themselves to those de¬ 
vised later. 

A very complete and exhaustive account of the 
various experiments made in securing the right con¬ 
ditions for railway motors and their application will 
be found in two papers written by Frank J. Sprague, 
a noted inventor in this line, for The Century Maga¬ 
zine, July and August, 1905. It adds to the interest 
of these articles that the author is fairly to be credited 
with perhaps the larger part of the inventions that 
have given us the electric-railway systems existing 
throughout the country to-day in the inter-urban 
trolley roads. Those who will give themselves the 
pleasure of reading these articles will find in them 
another illustration of what should be an accepted 
axiom, “ The way of the inventor is hard,” and will 
appreciate that between the theory formed by the 
cleverest inventor in his laboratory and the application 
of the same theory to the actual conditions met with 
outdoors there is a wide and howling wilderness 
filled with ravenous facts hardly less difficult to over- 


242 ELECTRICITY APPLIED IN ALL FIELDS 


come than the array of dragons and wicked enchanters 
that in the fairy stories are conjured up between the 
adventurous prince and the imprisoned princess. 

From the earliest experimental car that upon a 
specially built track a few hundred feet long in Berlin 
conveyed a dozen or two passengers, to the enormous 
trains that endlessly follow one another along the 
tracks of the New York Subway, packed to overflow¬ 
ing night and morning, there was a hill of difficulty 
only to be surmounted by skill, patience, and marvelous 
ingenuity, and the story of the surmounting of this 
hill is well told in the articles mentioned. Another 
good reason for referring to these articles is the fine 
series of illustrations showing photographs of electric 
railways from the crudest beginning to the modern 
forms. 

One hesitates to chronicle as an advance in civili¬ 
zation the adoption of the alternating current to the 
killing of criminals. In August of 1890 took place the 
first electrical execution at Albany. The use of the 
current for this purpose was advised after due consider¬ 
ation by an eminent board, but it has been fairly said 
in criticism that the only excuse made for this form 
of execution is based upon a pure assumption. Be¬ 
cause death from the electric current is apparently 
sudden, we assume that it is more merciful than older 
methods, but despite expert opinions we cannot know 
this ; and the only reason for being glad of the adop¬ 
tion of this method of execution lies in the fact that 
the popular interest in its novelty led to the publication 
of accounts of the first execution in such detail as to 
bring about a public sentiment demanding that this 
publicity should be stopped. A law was passed for- 



By courtesy of The Scientific American. 






















ELECTRICITY APPLIED IN ALL FIELDS 243 


bidding more than the publication of the fact that the 
criminal had been put to death. It is sincerely to be 
hoped that before many years the death penalty itself 
will be abolished. 

The year 1891, besides further study of the Hertzian 
waves and the patenting of the Berliner and Edison 
telephone transmitters, was notable for the successful 
transmission of electrical power in Germany, some¬ 
thing under eighty horse-power being transmitted from 
falls of the River Neckar. London in this year also 
followed the example of the Continental cities already 
mentioned in setting up permanent electric lights, the 
first in that city being in Victoria Street. A step 
tending to make the electrical units better known 
among experimenters was the printing of the report 
of the Electrical Standards Committee, an excellent 
preparation for the fuller discussion that was to take 
place at the Chicago World’s Fair two years later. 

By 1892 the amount invested in electrical work in 
the United States had increased by another hundred 
million dollars. The number of telephone connec¬ 
tions used also had increased by a hundred millions 
within two years, showing the enormously rapid spread 
of the telephone as a means of transacting business. 
The mileage of electric roads had reached about four 
thousand, and the use of the underground conduit for 
conveying the current was rapidly increasing. 

On October 18, 1892, Professor Bell sent the first 
message by telephone from New York to Chicago. 
In speaking of this accomplishment an article in 
Scribner's of the present year (1906) asks, “ What 
greater marvel is recorded in 4 The Arabian Nights ’ ? ” 

Another event of the same year, 1901, the impor- 


244 ELECTRICITY APPLIED IK ALL FIELDS 


tance of which was hardly then appreciated, was the 
exhibition by Nikola Tesla of his alternating current 
motor at the Royal Institution of London. This is a 
milestone from which to estimate the growth of the 
multiphase motors which began soon after to compete 
seriously with the direct-current motors then generally 
in use. 

Another discovery, the development of which even 
up to our own time has been far from exhausting its 
possibilities, was that of Arons, who showed that mer¬ 
cury vapor enclosed in a vacuum tube emitted light¬ 
waves, a discovery later developed practically by 
Cooper-IIewitt of New York in his well-known mer¬ 
curial vapor light. As Arons does not seem to have 
used the discovery practically, we shall postpone an 
account of its nature until we consider the Cooper- 
Hewitt lamps. 

In 1893, the year of the World’s Fair at Chicago, 
there was at that fair a meeting of a great electrical 
congress, and the exhibits in the electrical building 
gave a very good summary of the general state of 
electric science at that time. 

From an article in The Cosmopolitan describing the 
wonders of the World’s Fair at Chicago, we may get 
an idea of the awakening of the world to the achieve¬ 
ments already brought about by the applications of 
electricity and to the possibilities promised. Rightly 
enough, the author, Murat Halstead, gives first place 
in describing the wonders of the fair to the marvelous 
effects of the electric lighting, which must have im¬ 
pressed every visitor with the knowledge that man¬ 
kind had really doubled its hours of light. The reign 
of night had been overthrown. It is hard for us to 


ELECTRICITY APPLIED IN ALL FIELDS 245 


realize what it means to mankind to have secured the 
ability to make use of the hours of darkness precisely 
as if the sun was shining, to convert a vast area into 
a pleasure-ground available by night as well as by 
day. 

He next speaks of the electric launches, so impres¬ 
sive in their swift and silent power ; the railway cars 
that were moving by the same magical, soundless, 
and resistless force. Rightly, too, he speaks of the 
telephones that enabled one to “ talk to friends a 
thousand miles away and to enjoy the familiar charm 
of their voices and the magnetism of their presence.” 
All these marvels were due, he says, to “ the same 
mighty, subtle, delicate, formidable agency and mys¬ 
tery that permeates the atmosphere which compasses 
the universe.” And the great wonders he describes 
are actuated by “ but one breath of the all-embracing 
vital air, one sparkle of the surf that is the boundary 
of oceans, the great deeps beyond, unfathomable, but 
one may believe not unsearchable, not past finding 
out, but holding their treasures for the swift unfolding 
of the slow centuries.” 

While we are discussing the wonders of electricity 
with a mind mainly bent upon the method of their 
working we may well be glad to give a moment to 
such poetic sentences as these, in order that we may 
not forget the spiritual grandeur of the problems with 
which we are dealing. 

Nothing better shows the universal applications of 
electricity than even a brief list of its uses at the 
World’s Fair. It was electricity that turned its night 
into day ; that cast upon notable objects the unparal¬ 
leled emphasis of the searchlight; that by telephone 


246 ELECTRICITY APPLIED IN ALL FIELDS 


connected the whole nervous system of the adminis¬ 
tration into a single organism ; that enabled the police 
to supervise constantly every part of the grounds, 
that was ready at any moment’s notice to give the 
alarm of fire ; that turned the great wheels driving 
the marvels of mechanism ; that carried visitors from 
point to point and enabled them to fly as if upon a 
magic carpet from one end of the great fair to the 
other. 

One might go further and say that the fair itself 
was built by electricity, which sawed timbers, 
hoisted weights, ran the pumps, painted the buildings, 
lighted the grounds for night work. 

In addition to the uses mentioned, the electric rail¬ 
ways were guarded by a block system and provided 
with automatic braking devices to stop the trains in 
case of accident, and both these used electricity as 
their animating power. Another safety system used 
at the fair consisted of electrically lighted buoys 
pointing out the dangers of the shore from the Chi¬ 
cago River to the fair grounds. 

And to view all these applications of the new power 
the distinguished electricians of the world gathered 
from all civilized nations to receive at Chicago a 
widened view of the domain and of the possibil¬ 
ities commanded by their science. 

These men gathered in a congress similar to those 
which had before met at Paris and did rightful honor 
to the memory of Professor Joseph Henry by giving 
his name to a new unit, the unit of inductance. They 
also added to the value of the standards in use by de¬ 
claring a set of practical international units which 
have since been adopted throughout the world. 


ELECTRICITY APPLIED IN ALL FIELDS 247 


Apart from these general advances in the science, 
the more notable achievement of the year compre¬ 
hended a very great improvement in the storage bat¬ 
tery, tending to make it more economical and more 
lasting; the discovery that bv means of an electric arc 
formed under water metals could be melted by a heat 
so intense and so rapidly applied as to heat neither 
the water in which the contact is made nor any por¬ 
tion of the metal except that touched by the arc. It 
was suggested at once that this made it possible to 
temper small portions of steel tools where desired, 
without the need of hardening any more of the material. 

A fact that is perhaps more curious than significant 
was the inclusion of a whole electric equipment 
upon Nansen’s ship for arctic discovery, The Fram. 

Of much greater importance were two notable ad¬ 
vances in industry brought about by the use of the 
enormous heat of the electric arc. Means to apply 
this to various substances were devised by Professor 
Moissan of Paris, Siemens, and other investigators. 

The electric furnace may be divided into main 
types: those which produce the heat between two 
poles of a circuit (between which is an air-gap or 
space filled with some gaseous substance), producing 
their heat in the electric arc ; and those which pro¬ 
duce their heat in a poor or a narrow conductor con¬ 
necting the poles, thus slowing the vibrations and 
changing some of the electricity to heat. 

The first form of furnace consists essentially of a 
box made of chalk or of fire-clay with conductors, 
usually of carbon, passing through its walls. Within 
this box is placed the little crucible, which may be of 
carbon, magnesia, or'other substance not easily des- 


248 ELECTRICITY APPLIED IX ALL FIELDS 


troyed by heat. At times a little window of ruby 
glass is inserted, so that the work of the arc may be 
watched from the outside. There are also tubes ar¬ 
ranged through the walls of the box so that various 
gases may be allowed to enter if combustion is to be 
set up in some other gas instead of in air. 

The form of electric furnace known as the resist¬ 
ance or incandescent furnace, differs from the arc- 
furnace only in connecting the poles by means of a 
conductor of high resistance. The passage of the 
electric current heats this conductor, and the heat so 
generated is applied to any substance that may be 
piled over and around it, giving a less intense, but 
more controllable, heat where such is desired. 

If the poor conductor is a liquid solution we have 
still another class of furnace to consider. 

There is a very great variety of these electric fur¬ 
naces, but their heat always comes as in those already 
spoken of, from causing a current to pass from a good 
to a poor conductor. If the current has to pass an 
air space, an electric arc is formed and great heat is 
given out. If the current has to pass through a 
smaller (thinner) conductor, this becomes heated and 
may become incandescent. If the current passes 
through a liquid of high resistance (poor conducting 
power) the liquid likewise becomes hot. This gives 
the three great classes of furnaces: Arc furnaces, 
incandescent- furnaces, electrolytic furnaces. But 
all or any of these principles may be used in a single 
furnace. Then, too, there are cases when it is neces¬ 
sary to use an induced current (instead of a primary 
current) in the furnace, and this gives us an induction 
furnace. 


ELECTRICITY APPLIED IK ALL FIELDS 249 


We must be satisfied with the general principles 
here, since the applications are as numerous as the 
needs for various forms of heating. The uses of elec¬ 
tricity as a heating agent cover an enormous field, ex¬ 
tending from the use of a hot wire in medical practice 
to the working of great quantities of metal in enor¬ 
mous factories ; but all depend on the heating of a con¬ 
ductor through its resistance to the passing of the 
current. 

To give only a single example, by passing a current 
through coils of fine wire in a street car, the wires 
are heated, and the car is warmed. 

Another device should be explained as it has other 
applications besides its use in an electric furnace. In 
the early days of study of the electric art it was dis¬ 
covered that the arc itself acted as any current would 
act in the presence of a magnet — that is, it was de¬ 
flected from the magnet’s lines of force, according to 
the usual law of repulsion of currents. This property 
of magnets has been used even to deflect an arc 
enough to blow it out! In the electric furnace this 
property is used to direct, or deflect, the arc toward 
the place where it is to be applied. By means of the 
enormous heat, the greatest in the command of man, 
such refractory substances as platinum, carbon, and 
chromium can be readily melted, and thus new com¬ 
mercial substances unattainable in quantity in any 
other way have been really created. 

Among these we may mention carborundum and 
carbide of calcium, the second being the mineral from 
which by the mere application of water acetylene gas 
is obtained. It is true that acetylene had been known 
since 1830 and had been prepared in 1862, but, as the 


250 ELECTRICITY APPLIED IN ALL FIELDS 

“ Encyclopedia Americana ” says, u both it and the car¬ 
bide of calcium were laboratory curios until about 
1893, when the electric arc acting upon a mixture of 
lime and carbon produced the carbide in large quan¬ 
tities.” Carborundum (carbon and silicon) is made by 
heating; together in an electric furnace sand and car- 
bon. Discovered in 1891 by E. G. Acheson, the an¬ 
nual production of factories at Niagara Falls is now 
about five thousand tons. This substance is the 
hardest known excepting the diamond, and resists 
heat so completely that the inventor declares a layer 



A Carborundum Furnace 

This material, carborundum or carbide of silicon, is electrically produced by passing 
a current through a core of coke, surrounded by a mixture of carbon, sand, sawdust and 
common salt. It is commercially employed as an abrosive, for grinding wheels and as 
a substitute for emery, and is almost as hard as the diamond. 


one-twelfth of an inch thick will protect bricks 
against the highest temperature ever produced in 
ordinary work. 

To the credit of the electric furnace also must be 
put down the cheapening of aluminium, a metal the 
importance of which it is impossible to consider too 
seriously. Many great engineers, Nikola Tesla, for 
example, believe that the present age of iron will in- 




























ELECTRICITY APPLIED IN ALL FIELDS 251 


evitably be succeeded by the age of aluminium. We 
cannot here give the facts justifying the opinion. 

Though Sir Humphrey Davy attempted to obtain 
the metal, aluminium, early in the nineteenth century, 
it was first separated in 1827 by the chemist Wohler. 
This metal is, next to oxygen and silica, the chief 
component of the earth’s surface. It is even more 
abundant than iron. The metal was first obtained in 
fair quantity by Professor Deville, of Paris, who as a 
sign of his success presented to the infant Prince Im¬ 
perial of France, son of Napoleon III, a baby rattle 
made of this hitherto hardly known substance. By 
1860 aluminium was being made for eight dollars a 
pound and sold for twelve, and at this price it re¬ 
mained until about 1885. In that year, by using the 
electric furnace, the Cowles brothers of Cleveland, 
Ohio, produced cheap alloys of aluminium. Others, 
by improving the electric processes, succeeded in mak¬ 
ing five hundred pounds of aluminium a day. 

This was about 1886, but as soon as the electric proc¬ 
esses of manufacture were applied to the metal its 
price was brought steadily downward, and within ten 
years the works at Niagara Falls were producing 
about ten thousand pounds a year. Its price in 1902 
was about thirty cents a pound. 

Electrically considered, though its resistance is 
greater than that of copper, yet for the same weight 
the resistance is the same. In regard to its use as a 
conductor, Tesla says : “ It is cheaper to convey an 

electric current through aluminium wires than through 
copper wires.” He believes that the aluminium indus¬ 
try will annihilate the copper industry and will pass 
on to a struggle for commercial supremacy with iron. 


252 ELECTRICITY APPLIED IN ALL FIELDS 


Which will prove conqueror depends upon whether 
the magnetic power of iron continues to make it indis¬ 
pensable in electric machinery. If these properties 
can be dispensed with, says Tesla, “ iron will be done 
away with and all electric machinery will be manufac¬ 
tured of aluminium at prices ridiculously low. This 
would be a severe, if not a fatal blow, to iron.” 

We cannot refrain from quoting a few more words 
from Tesla’s article entitled “The Problem of Increas¬ 
ing Human Energy,” in The Century Magazine for 
June, 1900. “ There can be no doubt,” he says, “ that 

the future belongs to aluminium, and that in times to 
come it will be the chief means of increasing human 
performance. I should estimate its civilizing potency 
at fully one hundred times that of iron. . . . We 

must remember that there is thirty times as much 
aluminium as iron in bulk available for the uses of 
man. It is more easily workable, it partakes of the 
character of a precious metal, its electric conductivity 
for a given weight is greater than that of any other 
metal, which alone is sufficient to make it one of the 
most important factors in future human progress. Its 
extreme lightness makes it far more easy to transport 
the objects manufactured.” And this great gift to 
mankind may be credited solely to the use of electric 
energy, either in electrolysis or in the electric fur¬ 
nace. 

The extension of telephony to include a commercial 
line from New York to Chicago was a notable event 
of the World’s Fair year. 


CHAPTER XXI 


ELECTRIC WAVES AXD RAYS 

The year 1894 was notable principally for the be¬ 
ginning of the experiments of Marconi in practical 
wireless telegraphy, experiments which to-day may be 
considered successful in adapting wireless telegraphy 
to practical use. This young Italian was born near 
Bologna. He was the first to perfect the appliances 
used in space telegraphy and the first to patent the 
application of the Hertzian waves to actual telegraphy. 

It was also in 1894 that Professor Oliver Lodge, in 
demonstrating wireless telegraphy before the Royal 
Institution of London used the Branly coherer of iron 
filings in a glass tube in order to detect the waves and 
to make them close a circuit operating a bell. He im¬ 
proved the apparatus, by combining with it a so-called 
“ tapper,” a little hammer operated either by clock¬ 
work or electricity, that by striking the coherer re¬ 
stored the filings to the looser contact. 

An advance of this year, 1894, in telephony was the 
centralizing of all the batteries in a single exchange 
for each telephone district, instead of employing sepa¬ 
rate batteries in the house of each subscriber. 

The year 1895 was rather a remarkable one in the 
history of electrical development. The great increase 
in electrical devices and competition of various com¬ 
panies in making them, had caused a fall of their 
prices, and this widely extended their use. It also at¬ 
tracted to the businesses relating to electricity a higher 

253 


254 


ELECTEIC WAVES AND EAYS 


class of talent and generally stimulated the science and 
art as commercial success naturally would do. 

The World Almanac for 1896 declares that money 
in 1895 would buy nearly ten times the value in elec¬ 
trical supplies that the same money would have- 
bought ten years before, and this with an improve¬ 
ment in quality. A third reason for the electrical 
prosperity was the increasing confidence of capitalists 
in the art. Fully fifty millions of dollars of new capi¬ 
tal was this year devoted to electrical, enterprises. 

To take up the different fields in order — The tele¬ 
phone was greatly extended, though without any 
especially notable improvement. In telephony, the 
expiration of certain of the Bell Company patents 
brought many new competitors into the field. This 
naturally increased the number of exchanges and im¬ 
proved the service. In this year also was established 
a system of charging according to the use made of 
the instruments, instead .of at a fixed rate. In New 
York the telephone circuits were entirely metallic — 
that is, wires were used both for the outgoing and 
incoming current instead of connecting lines to the 
earth. 

In electric light no great novelty appeared, though 
much was expected from the inventions of Tesla — an 
expectation that was disappointed because of the de¬ 
struction of the inventor’s laboratory by fire. In the 
use of electric power the history of the world was one 
of general extension to various manufacturers, the in¬ 
stallation of many electric elevators, and particularly 
of electric fans in large numbers. A device that 
found much use in mining was that of the chain- 
cutter, an endless chain provided with blades and 



Scteur/r/c ‘ 


13,000 Horse-Power Turbine for the Electric 
Development Company, of Ontario, Ltd. 

By courtesy of J'he Scientific American. 























ELECTEIC WAVES AND EAYS 


255 


operated by an electric motor so as to bring the 
knives, or cutters, in contact with a vein of coal. 

But the most important development of the year 
was in the transmission of power which resulted from 
a combination of dynamos with water-power driving 
water wheels, and thus generating electricity from the 
cheapest source of electric energy. The limit of 
distance for that time was thirty miles. The Niagara 
Falls Power Company of this year completed its great 
plant for the purpose of supplying practically un¬ 
limited power derived from the falls. It is estimated 
that the power available amounts to perhaps seven 
million horse-power. 

The method adopted for changing gravity energy 
of the falling water into electric currents may be 
generally described as follows : A canal was dug 
extending from the river about a mile above the falls. 
Parallel to this was a wheel-pit, 178^2 feet deep and 
425 feet long. This wheel-pit was connected by a 
tunnel with the river below the falls. In the wheel- 
pit were . set up ten turbine wheels weighing a 
hundred and fifty thousand pounds each. The water 
entering the wheels from below tends to lift them and 
makes them run without friction so far as their weight 
is concerned. To the shaft of the turbines were con¬ 
nected alternating-current dynamos which yielded the 
current that, properly changed by transformers, could 
be conducted where desired and then retransformed 
to serviceable condition. 

The electric railway came more and more into use 
during the year, in many cases superseding horse cars 
in entire cities and also showing signs of replacing 
even the steam locomotive upon shorter suburban lines. 


256 


ELECTRIC WAVES ARD RAYS 


The World Almanac , which gives an excellent sum¬ 
mary of these facts, ends its article with this state¬ 
ment : “ Taken altogether, electrical developments of 

1895 have resulted in a vast increase in the convenience 
and economy with which many of the tasks neces¬ 
sary to comfortable existence may be accomplished.” 

But even that summary makes no reference what¬ 
ever to probably the most important discovery of the 
year—the Roentgen or x-rays. 

In 1895 Professor Roentgen of the L T niversity of 

Wurzburg announced the dis¬ 
covery of certain new rays of un¬ 
known nature which he named 
“ x-rays ” because they were an 
unknown quantity like x in 
algebra. His discovery came 
about while he was making ex¬ 
periments in passing the electric 
current through a glass tube 
which had been exhausted nearly 
to a vacuum, and in order that we 
may understand something of his 
work, we must recall certain 
studies upon the subject. 

When a glass tube is ex¬ 
hausted until the air pres¬ 
sure has been reduced to Ttshns of the usual pressure, 
and then a current is passed through wires fused into 
it, there are some striking appearances produced. A 
glow of light appears at the cathode wire (the nega¬ 
tive or “ outgo ” wire), next to it is a dark space, and 
then a glowing space. The glass near the cathode 
>also glows with a vivid phosphorescence. The cause 



The Crookes Tube, for 
Producing the Ko- 
ENTGEN OR X-RAYS 










ELECTRIC WAVES AND RAYS 


257 


of these effects was studied by a number of experi¬ 
menters from 1859 to 1879 and about the latter 
year was well explained by Sir William Crookes 
of England. The “cathode rays” were thought 
to be caused by something coming from the cathode, 
since a substance put in them caused a shadow 
on the opposite side of the tube, and this shadow 
also showed the path of the rays to be straight 
from the cathode surface. A concave cathode sur¬ 
face was found to concentrate the rays as a con¬ 
cave mirror concentrates light rays. These rays 
have a strong heating effect, and also act with 
mechanical force to push an obstacle from their 
path. Sir William Crookes caused them to push a 
little wheel with paddles along rails within the tube. 
They also cause the glass tube to show phosphorescence 
where they strike on it, and they make the air or other 
gas in the tube a conductor of electricity. 

But, most important of all, the cathode rays were 
found to be turned from their path by an electric or 
magnetic field of force — acting as the electric current 
acts in the same circumstances. Hence arose the 
theory that the cathode rays were particles of gas 
negatively charged with electricity and repelled with 
great velocity from the cathode since it also was in 
the same electric condition. This was the view of the 
English. But the Germans saw no reason to believe 
there were moving particles in the cathode rays, con¬ 
sidering them only ether waves. 

Heinrich Hertz in 1892 strengthened the German 
view by showing that the rays would pass through 
gold leaf, which seemed hard to explain by the Eng¬ 
lish theory. Lenard, an assistant to Hertz inserted a 


258 


ELECTEIC WAVES AAD BAYS • 


bit of aluminium in the walls of the tube, and direct¬ 
ing the rays upon this “ window” brought them out 
of the tube, where they became known as “ Lenard 
rays.” 

But then Professor J. J. Thomson showed in 1897 
that the deflecting of the rays proved them, probably 
to be particles negatively electrified or to carry a 
charge of electricity with them. Further experiments 
by the same brilliant philosopher measured the masses 
of these particles, their velocity, and the charges car¬ 
ried by them — and their ability to pass through sub- 
tances was explained. It was because of their 
minuteness and their almost inconceivable speed of 
motion. Ilis experiments were carried on in England 
with the most elaborate care and are well worth the 
closest attention by students who wish to understand 
the modern theories of matter. But here we cannot 
enter fully into them, and must refer the reader to 
more technical books for the details and proofs of 
Thomson’s conclusions. And for a most interesting 
account of.the conclusions to which Thomson’s experi¬ 
ments lead the reader cannot do better than to ex¬ 
amine the lecture by Sir Oliver Lodge, delivered at 
Oxford in June, 1903. This lecture is published by 
the Clarendon Press and is reprinted in the Govern¬ 
ment Eeport of the Smithsonian Institution for 1903, 
to be found in the libraries. 

In speaking of these experiments the lecturer declares 
that the researches may be said to constitute “the 
high-water mark of the world’s experimental physics 
during the beginning of this century.” 

The conclusions drawn by Sir Oliver Lodge are 
that the so-called smallest possible material body, the 


ELECTRIC WAVES AND RAYS 


259 


atom, has been shown to be divisible; that the so- 
called electrons can be separated from atoms, that the 
atom may possibly be built up of positive and negative 
electrons and of nothing else. These electrons are to 
be thought of as flying about inside the atom, forming 
a kind of cosmic or solar system of inconceivable 
minuteness and occupying an otherwise empty region 
of space which we call the atom, “ as a few active 
soldiers might occupy a large territory, by incessant 
activity rather than by bodily numbers or bodily 
bulk.” Whether the electron has a nucleus of matter 
within it is still doubtful. 

This theory agrees with the claims always made by 
Crookes himself — that the matter in these tubes was 
in a new state, in a fourth state (1 solid, 2 liquid, 3 
gaseous, 4 new), which he called “ radiant matter.” 

It is a stream of these electrons—those charged 
negatively — that make up the cathode rays, and in 
investigating these cathode rays Professor Roent¬ 
gen found that there was produced at the same time 
another kind of rays that were invisible, not deflected 
by a magnet, and yet would readily penetrate many 
solids opaque to ordinary light and solids that stopped 
the cathode rays. 

In order to give an idea of the supposed relative 
size of these electrons compared with a single atom of 
hydrogen, we shall quote another paragraph from Sir 
Oliver Lodge, who said : “ If we imagine an ordinary 

sized church to be an atom of hydrogen, the electrons 
constituting it will be represented by about seven 
hundred grains of sand, each the size of an ordinary 
full stop [a period], three hundred and fifty positive 
and three hundred and fifty negative, dashing in all 


260 


ELECTEIC WAVES AND EATS 


directions inside, or, according to Lord Kelvin, rotating 
with inconceivable velocity. . . . The extreme 

minuteness and sparseness of the electrons in the atom 
account for their penetration. Electrons will pass 
almost unobstructed through ordinary opaque bodies.” 

Professor Eoentgen having covered a vacuum tube 
lighted by cathode rays with black paper, so that no 
visible rays appeared, these x-rays were not interrupted, 
but came out of the tube through the paper so as to 
illuminate and make phosphorescent a sheet of paper 
properly prepared with certain chemicals. This paper 
had been prepared for use with the cathode tube, and 
was accidentally near. The x-rays were subjected to a 
number of experiments and their properties ascertained. 
The most striking of these was their ability to affect 
the photographic plate while it was covered by the 
usual plate-holder, impassable by ordinary light. 

By trying different substances in the rays, it w T as 
found possible to separate them into classes in regard 
to their transparency toward the new dark light. It 
was soon seen that a most valuable new agency had 
been discovered. Professor Eoentgen believed that 
the rays were the so-called “ longitudinal ” rays of light 
whose existence had been conjectured by scientific 
men, notably by Lord Kelvin. 

The meaning of longitudinal in this sense is that the 
rays are supposed to vibrate from and toward the 
source of x-rays rather than transversely across the 
path of the beam, as in ordinary light. Since bones 
are less transparent to these x-rays than is flesh, it was 
at once seen that the rays would enable a surgeon to 
photograph the bony structure through the flesh, and 
for this purpose they were early used. 


ELECTRIC WAVES AND RAYS 


261 


The applications of the discovery have been too 
numerous to be easily mentioned here, extending from 
such uses as discovering false diamonds by their trans¬ 
parency being less than that of the real stones to the 
revealing of smuggled goods inside of closed boxes, 
which has been done in custom-houses. 

In order to avoid the necessity of taking the pho¬ 
tographs, in 1896 an Italian, Professor Salvioni, coated 
a screen with a phosphorescing compound, platino- 
cyanide of barium, and affixed to the screen a box and 
eye-piece so that the observer could look through 
the screen, the outer light being excluded. If a hand, 



The Fluoroscope 


for example, were interposed between the source of the 
x-rays and the screen, an observer looking at the 
screen could see upon it shadows of all substances 
that interfered with the transmission of the x-rays. 

A similar “ fluoroscope,” or “ fluorescent screen,” as 
the apparatus is called was afterward made by 
Thomas A. Edison to view the shadows. It should 
be explained, however, that “ shades ” rather than 
shadows, is the right word, since nearly all substances 
are more or less traversed by the rays and hence the 




262 


ELECTRIC WAVES AND RAYS 


rays are not often stopped entirely as in making a true 

shadow. Edison improved the fluoroscope by using 

calcium tungstate as the coating, which gave better 

results than the substance used by Salvioni. Other 

«- 

« 

substances have since been used, and there have been 
many improvements in the machines for producing 
directing, and photographing these radiographs or 
“skiagraphs” cast by the new rays. 

Professor Elihu Thomson discovered that the x-rays 
can pass through and act upon a mumber of photo¬ 
graphic plates at once, giving multiplied images with 
one exposure. The action of these rays upon the 
human skin when allowed to affect it too long or too 
closely is at times harmful or even destructive, and 
this has led to the invention of means for directing, 
restraining or modifying its influence. 

It was in 1895, also, that Nikola Tesla brought out 
his electric oscillator, a means for producing a rapid 
alternating electric current by a combination of the 
steam engine and the electric motor. Essentially, this 
apparatus consisted of an engine that plunged a piston 
into and withdrew it from, a coil, with enormous 
rapidity and thus caused in the coil alternations of 
electric potential that induced a current of great 
frequency. It was, in fact, an induction machine, the 
interrupter of which was a piston driven by steam. 

So rapid was the development of the use of the 
x-ray in 1896 that there were ten firms engaged in sup¬ 
plying apparatus for producing the rays to hospitals, 
physicians and investigators. Such men as Edison and 
Tesla gave much of their time during the year to the 
improvement and study of devices connected with the 
new discovery. 


ELECTRIC WAVES AND RAYS 


263 


In telegraphy an interesting feat occurred during the 
great electrical exhibition held in New York City in 
May, a cable message being dispatched around the 
world from one end of the building where the exhi¬ 
bition was held and received at the other. The trans¬ 
mitting operator was A. B. Chandler, president of the 
Postal Telegraph Company, and the message w^as 
received by Thomas A. Edison. 

The telephone continued to increase in popular favor 
and was reduced in price and extended in the distance 
covered. For “ all practical purposes the whole country 
east of the Mississippi River was one vast telephone 
exchange.” The presidential election gave the tele¬ 
phone companies an excellent opportunity of demon¬ 
strating the swiftness and ready distribution of news 
by means of the telephone, giving the returns in this 
way to some twenty thousand people in private resi¬ 
dences in New York City even before the results were 
known in the very towms from which the returns came. 
Generally speaking, the telephone news was half an 
hour in advance of the telegraph. 

Another interesting exhibition of telephony was the 
setting up of a transmitter in the Cave of the Winds 
at Niagara from which the roar of the falls was 
brought within hearing of visitors to the electrical 
exhibition in New York City. 

In electric lighting, a second globe was placed about 
arc lamps, a great advance in the art of arc-lighting. 
The second globe made the carbons last longer, im¬ 
proved the distribution of light, and also lessened dan¬ 
ger from falling sparks. A new system of lighting by 
means of vacuum tubes excited by the alternating cur¬ 
rent to luminosity was devised and exhibited by Pro- 


264 


ELECTRIC WAVES AND RAYS 


fessor D. McF. Moore, and has come into use especially 
for advertising purposes. 

The use of electric power commercially continued to 
extend in all directions, and on the 16th of November 
electrical energy equaling one thousand horse-power 
was transmitted from the works at Niagara Falls to 
Bulfalo, twenty-six miles away, and there used for 
driving street cars. 

The means of transmission from the falls to the 
city limits was by bare copper wires insulated on por¬ 
celain. Then underground conduits brought the power 
into the city. In the electrical exhibition in New York 
a small model of the Niagara Falls works was put in 
operation by means of one-thirteenth of a horse-power 
transmitted over four hundred and fifty miles from the 
falls itself. The next longest previous transmission 
of power was about a hundred and ten miles. 

In electric railways there was large increase in the 
number of roads operated and in their economy. A 
Chicago railroad claimed to save ten thousand dollars 
a month over the cost of steam power. Thus, although 
the year 1896, a presidential year, was the worst busi¬ 
ness year in the history of the industry, to quote from 
The World Almanac , there were many signs of steady 
progress. 

In 1897 Edison announced the completion of his mag¬ 
netic process for separating iron from its ore. This is 
done by crushing the ore to a finely-divided state, 
hoisting it to the top of a high building, and then al¬ 
lowing the crushed ore^ to fall in front of the poles of 
magnets. The attraction of the magnets draws the 
particles of iron toward them and they are thus caused 
to fall nearer to the magnets than the rest of the 


ELECTRIC WAVES AND RAYS 


265 


powdered ores. A fence is so placed as to separate the 
iron from the waste product. This, like some others 
of Edison’s inventions, illustrates no new principle, but 
is merely an ingenious man’s adaptation of well known 
principles to commercial purposes. The idea of sepa¬ 
rating iron from the ore may not have been entirely 
new or the method original solely with Mr. Edison, 
but its application upon a commercial scale and its 
commercial success may be credited to him. 

So far as telegraph and telephone were concerned, 
the chief event of importance was the removal of 
overhead wires from down town, New York, to under¬ 
ground conduits, a most desirable improvement made 
possible by the better knowledge of means for securing 
perfect insulation. There were no startling novelties 
introduced during 1897, the history of the year being 
one of generally increased improvement in the already 
well established industries and enterprises dependent 
upon electricity. 

New York City saw the beginning of an electric 
cab service, a result due to the improvement of the 
storage battery. The storage battery system of pro¬ 
pulsion is especially adapted to cab service, since these 
vehicles can always be within reach of electric stations 
from which they can obtain new batteries. 

To the discovery by Dr. Carl von Welsbach that 
certain rare elements when brought to a state of in¬ 
candescence gave out a very brilliant light we owe the 
gas mantles now so commonly seen in the Welsbach 
burner, a device that, according to Robert Kennedy 
Duncan in an article published in Harper's Magazine 
in August, 1906, was the salvation of the enormous 
gas industry. 


266 


ELECTRIC WAVES AND RAYS 


In order to study these incandescent minerals, 
Welsbach had dipped a bit of cotton fabric in their 
solutions and afterward held it in the dame of a Bun¬ 
sen burner. “ It did increase the incandescence,” says 
Professor Duncan, “ but it did more; the cotton burned 
away leaving a skeleton fabric made of the oxides of 
the elements, and this skeleton glowed with a brilliancy 
and a beauty that were astonishing.” From this ac¬ 
cident came the invention of the Welsbach mantle. 
But these rare earths, as Professor Duncan puts it, 
were not only “ sauce for the goose ” in saving the 
gas industry, but “sauce for the gander” in improving 
electric lighting. 

In 1897, Professor Nernst, of Gottingen, showed 
that while a dlament made of these rare substances 
was at ordinary temperatures a non-conductor of 
electricity, when heated even by the burning of a 
match, their conductivity increased and kept on in¬ 
creasing. To quote again : “ It is very like one of 

the Holland dams. So long as the dam is perfect the 
dam is safe — it is a non-conductor of water — but 
permit the smallest hole, no larger than a dnger, upon 
which the water may work, and, shortly after, the 
resistance of the dam has broken down and the whole 
volume of the current washes through. The cold 
dlament made of these earths offers an impenetrable 
resistance, but at 600° C. a little current passes. This 
makes the dlament hotter, which allows more current 
to pass, which makes the dlament still hotter, which 
permits still more current, which makes the dlament 
hotter again, and so it builds itself up until it arrives 
at a semi-pasty condition when practically the whole 
of the current passes through, and it shines with a 


ELECTRIC WAVES AND RAYS 


267 


very vivid and very beautiful incandescence. This is 
the basis of the Nernst lamp.” 

But the full development of the lamp, and of similar 
lamps using rare elements, did not take place for 
several years. 

The year 1898 saw a very marked improvement in 
the application of electricity to street railways and 
other forms of traction. The electric cab system had 
proved successful, street railways were being electric¬ 
ally equipped everywhere, and the long distance rail¬ 
ways were making inquiries as to the relative advan¬ 
tages of steam and electricity and in some cases had 
decided to equip their lines for the latter power. 

This year of the Spanish War produced, of course, 
a sudden and enormous demand for electric devices. 
The coast of the United States was protected by thou¬ 
sands of submarine mines and by extra systems of 
communication, all of which required thousands of 
miles of wire, and there was a similar sudden demand 
for trained men capable of supervising governmental 
electric installations. This demand led to the forma¬ 
tion of a corps of Volunteer Engineers, mainly of 
electricians, who under pressure showed themselves 
rapid and accurate workmen. 

The medical department of the Army called for x-ray 
machines in large mumbers ; the Navy, already fitted 
with electrical devices for turning the turrets of war¬ 
ships, for hoisting ammunition, for lighting, signaling, 
and the operation of the great search-lights, also in¬ 
creased the demand for electrical work and supplies. 
So that the year was one of great profit and rapid 
progress in electrical industries. 

Another secondary effect of the war was the stimula- 


268 


ELECTEIC WAVES AND BAYS 


tion of the telegraphic service, some of the largest 
newspapers expending from one thousand to fifteen 
hundred dollars a day for despatches. Meanwhile a 
sympathetic increasing interest in electrical industries 
brought about a very successful electrical exhibition at 
Madison Square, New York, and here, as well as at 
Omaha, Pittsburg, Philadelphia and Chicago, where 
various exhibitions were held, the electric light was 
applied in many novel and beautiful ways to form 
decorations. 



A Thirty-inch Searchlight at Work 


The application of the search-light to warfare had 
proved its enormous value, the blockade of Cervera’s 
fleet at Santiago being made effective by the concen¬ 
tration of searchlights on the harbor entrance, which 
not only revealed every movement of the enemy, but 
also blinded the eyes of Spanish watchers to the pro¬ 
ceedings of the American fleet. 

As a defense against torpedo craft the search-light 
in combination with small rapid-fire guns proved en¬ 
tirely effective, the efforts of the Spanish boats to 
approach the Americans being completely futile. 

























ELECTRIC WAVES AND RAYS 


269 


Equally successful was the transmission of power 
on board the warships from central power installations 
on shipboard, and the various applications to mechan¬ 
ical work — to guns, pumps, doors of compartments, 
and so on; the great advantage of the electric power 
for all such purposes lying in the fact that if the wires of 
communication are cut, they are readily repaired, and 
at the same time their cutting produces no damage to 
speak of as contrasted with the terrible results caused 
by the bursting of pipes carrying hot steam. In 
signaling, the search-light, combined with the wigwag 
system, proved most useful and was applicable to great 
distances. 

Turning to the triumphs of peace, it may be recorded 
that the amount of power transmitted from Niagara 
Falls rose to sixty thousand horse-power, and the 
growth of power plants was especially marked in the 
newer parts of country, in the West, where their value 
depended largely upon the fact that water-power was 
often available at considerable distance from the 
manufacturing or transporting centres where it was 
needed. 

The telephone, with 270,000 subscribers and four 
hundred and twenty thousand miles of wire, was im¬ 
proved by the adoption of the new switchboard, 
wherein the lighting of tiny glow-lights warned the 
operators whenever a subscriber was through with his 
communication. In distance the record was twenty-six 
hundred miles, from Austin, Texas, to Bangor, Maine. 

There were also three advances in the theoretical 
study of electrical communication, due respectively to 
Marconi, Tesla, and the late Professor Rowland of 
Johns Hopkins University. Marconi, having erected 


270 


ELECTRIC WAVES AND RAYS 


vertical wires from eighty to a hundred feet high, by 
the use of an induction coil giving a spark ten inches 
in length, was able to transmit waves through space 
to a distance at first of forty miles, and afterward, by 
using higher vertical wires, of two hundred and eighty 
miles over water. These waves were received by 
means of the Branly and Lodge coherer, thus operat¬ 
ing: receiving instruments. We shall describe this 
system a little later, after speaking of the other two 
methods of communication. 

Tesla announced the result of certain researches 
proving that several miles upward the air, becoming 
rarefied, ceased to give great electrical resistance and 
became an excellent conductor. This is already ap¬ 
plied to a system of telegraphing by means of balloons. 
Sending up two balloons at a distance from one 
another, each about five miles high, he transmitted a 
current through a wire to one of the balloons, 
where, by means of transformers the current was made 
one of high potential capable of sending waves through 
these conducting layers of upper air. These waves 
being received by the other balloon, were again trans¬ 
formed by instruments which it carried, and trans¬ 
mitted by a wire to the earth, where they operated a 
telegraph receiver. 

Tesla during the same year, announced and illustrated 
by a model, the possibility of building a self-operated 
vessel which he named the “ telautomaton.” A storage 
battery placed within furnished motive power. A 
propeller driven by a motor enabled it to go in any 
direction when steered by a little motor operating the 
rudder. The control of his boat was accomplished 
by an electric circuit operated by electric waves sent 


ELECTRIC WAVES AND RAYS 


271 


through space, the circuit being tuned so as to respond 
only to certain waves of determined length. These 
waves were furnished by his electric oscillator. This 
tuning is accomplished by attaching plates of metal 
to the discharging points of an induction-coil — the 
size of the plates governing their vibration. 

Tesla’s purpose in making his model was to show 
that warfare might be carried on by means of auto¬ 
matic vessels, or rather mechanisms, while the operators 
remained far from the danger zone. 

In speaking of his invention in The Century Maga¬ 
zine for June, 1900, Tesla says: “ There, is virtually 
no restriction as to the amount of explosive which can 
be carried or as to the distance at which it can strike, 
and failure is almost impossible. ... Its advent 
introduces into warfare an element which never ex¬ 
isted before — a fighting machine without men as a 
means of attack and defense.” Of course there has 
been no public application of this principle upon a 
large scale. 

Professor Rowland’s system of telegraphy was an 
improvement of what is known as the synchronous 
system—which has been tried in various forms by 
numerous inventors. The general principle underlying 
it may readily be explained. 

Suppose a conducting wire to be extended from 
station A to station B. At the station A end of this 
wire is a revolving wheel against the side of which 
the wire touches. Upon the wheel are a number of 
segments radiating from the centre. As the wheel 
revolves the conducting wire touches one of these at 
a time, then passes on to the next, and so on around 
the circumference. On the opposite side of the wheel 


272 


ELECTRIC WAVES AND RAYS 


are as many wires as there are segments, each ar¬ 
ranged so as to touch only its own segment and none 
of the others. A similar arrangement is at the other 
end of the line at station B. If the two wheels are 
turned at the same rate so as to make the same seg¬ 
ments touch the conducting wire between stations at 
the same time, it is easy to see that the wheels will con¬ 
nect each one of the pairs of wires successively with 
the conducting wire, A with A, B with B, and so on. 
Consequently the conducting wire becomes a part of 
each pair of wires in turn, completing their circuits. 
If an operator sends an electric impulse over his wire, 
it will be conducted to the other station and received 
by the corresponding wire at the instant when the 
two wheels cause the conducting wire to join this 
pair. 

If, now, the wheels revolve so as to turn completely 
round once or more during the time an operator is 
holding down a key, every touch of a key will send an 
impulse over the conducting wire. It will be seen 
that, in theory, it is quite possible to use a single wire 
thus successively for a large number of messages, since 
it is easy to revolve the wheel fast enough so that it 
will make a single turn or more during the depression 
of a key. 

Unfortunately there occur certain practical diffi¬ 
culties in applying the s} T stem to use, and though these 
have been to a certain extent overcome by a number 
of systems, and the multiplex system has been put to 
good use, it has never proved in all respects a success¬ 
ful competitor with its rivals in practical telegraphy. 
One of these difficulties is that of assuring exact har¬ 
mony in the revolving of the wheels, especially at high 


ELECTBIC WAVES AAD EAYS 


273 


speeds. A second difficulty consists in the slowness of 
getting rid of previous electric currents in the con¬ 
ducting wire. If the messages follow one another 
very rapidly over this wire there is danger of previous 
messages interfering with later ones because the elec¬ 
tric charge has not been cleared from the conducting 
wire. 

A system of this sort used in Great Britain is known 
as the Delany system. It controls the motion of the 
revolving wheels, insuring a uniform rate, by electric 
motors at each station, these being governed by tuning- 
forks or vibrating reeds. In the Delany wheel there 
are eighty-four segments, insulated from one another, 
and the connection with the conducting wire is by 
means of a trailer which rests on the wheel. The 
wheel makes three revolutions a second, and conse¬ 
quently each segment touches the trailer three times a 
second. But to secure more frequent contact, more 
than one segment is connected with each pair of wires 
or lines through which the telegraphy is to be accom¬ 
plished. Thus, to send six messages by the same wire, 
six segments are put into communication with the same 
pair of wires; consequently, at each revolution, this 
pair of wires is made to connect with the main con¬ 
ducting wire thirty-six times a second. The five other 
pairs of wires may also have six segments apiece, mak¬ 
ing thirty-six segments used for transmission in the 
six lines. 

Another thirty-six segments in the same way are 
connected to the six different pairs of wires, using al¬ 
together seventy-two out of the eighty-four segments to 
connect the six stations at each end, each station thus 
being provided, thirty-six times a second, with a com- 


274 


ELECTRIC WAVES AND RAYS 


plete transmission circuit, and also with a complete 
receiving circuit thirty-six times a second. 

To make an ordinary dot in telegraphy takes about 
one-twelfth of a second, and during that time the 
revolving wheel (or the revolving trailer, for it makes 
no difference which revolves) will have connected the 
transmitter three times with the main line, each of 
these connections being independent of those given to 
the other operators at their six desks. The remaining 
segments, those not used for telegraphy, operate the 
mechanical devices that keep the two wheels or two 
trailers revolving synchronously, or at a uniform 
rate. 

This system, invented b}^ P. B. Delany, an improve¬ 
ment of earlier forms, is used in Great Britain. 

Professor Rowland’s system was announced by him 
to be capable of transmitting twelve messages each 
way at once, but its latest form transmits four in each 
direction at the same time. He used two cylinders 
bearing segments connected, like those in the Delany 
system, with separate pairs of wires, and the main 
principle is very similar. In brief, the general prin¬ 
ciple is simply to place a conducting wire successively 
between a pair of wires, and then between a second 
pair and a third pair, and so on, connecting each pair 
only for an instant and then being moved to the 
next. 

Another system of multiplex telegraphy, that has not 
been hitherto explained, operates by means of tuned 
receivers. Over a single wire are sent, from tuned 
transmitters, a number of electric waves vibrating at 
different rates. At the receiving station are a number 
of ribbons of steel, each tuned, like the strings of a 


ELECTRIC WAVES AND RAYS 


275 


musical instrument, to vibrate only under the in¬ 
fluence of a particular note. When the composite 
musical tone arrives on the main wire each ribbon 
responds only to the vibrations to which it has been 
tuned, and the ribbon, when vibrated, actuates a re¬ 
ceiving instrument. This has not been described 
because it has not come into extended commercial 
use, owing to the practical difficulties in its operation, 
and the space we can give to each of the later applica¬ 
tions of electricity will not admit of noticing more 
than a few important and practical systems. 

In speaking of the Marconi system of wireless teleg¬ 
raphy, while we must give to the Italian inventor all 
due credit for the devising and putting into practical 
shape of the system now so generally used, it should 
be recorded in every account of the art that the first 
wireless telegraphic communication was made by 
Professor Popoff, of Russia, who, in April, 1895, de¬ 
scribed to the Russian Physical Society a practical 
system. The production of the waves was by the 
same method used by Hertz, namely, an induction 
coil that produced sparks between two ball conductors 
and thereby caused electrical waves to be propagated 
in all directions about the instrument. Professor 
Popoff’s receiver consisted of a vertical wire connected 
with a coherer which, in turn, was connected with the 
earth and also with a local circuit at the receiving 
station. This local circuit included a voltaic battery 
that operated an electro-magnet, and this moved a 
relay lever. The coherer was the ordinary tube of 
metal filings. When an electrical wave caused the 
filings to cohere, a current passed from the battery, 
operated the relay, and caused the closing of a circuit 


276 


ELECTRIC WAVES AND RAYS 


containing a battery. This battery operates a receiv¬ 
ing key, at the same time ringing an electric bell, and 
also with the same hammer striking the tube of iron 
filings and shaking them apart so that they are ready 
for another impulse. 

The Popoff apparatus was not entirely perfected, 
but it will be seen that since it existed as far back as 
1895, the essentials of the system were then under- 



Diagram of tiie Popoff Wireless Telegraph Receiver 

A vertical “exploring” wire V is connected with the ground through the coherer C, 
which in turn is connected with a battery circuit and a relay R. This relay closes the 
circuit of another battery, not shown in this diagram, which is connected with a bell B 
and with the recording instrument. When the coherer is influenced it closes the latter 
circuit, actuates the recorder, and thus makes a record. The bell at the same time taps 
the coherer-tube, and thus breaks the circuit of the coherer by causing the filings which 
compose its filling to fall apart. 


stood. Marconi's system was completed, in its first 
form, in March, 1897. Professor Houston points out 
the resemblance between the Popoff and Marconi 
systems, but declares that Marconi was probably 
ignorant of what Popoff had already accomplished. 

Marconi’s system did not differ essentially from the 
other forms, being only an induction coil that pro- 
























































ELECTRIC WAVES AND RAYS 


277 


duced sparks. His receiver used an improved coherer, 
being a glass tube closed by two pieces of silver only 
one-twenty-fifth of an inch apart, between which were 
pure nickel filings with a slight addition, four per cent, 
of silver filings. A little mercuiy was mixed with them 
to increase their sensitiveness. In this coherer tube a 
moderately high vacuum is produced, an improvement 
due to Sir Oliver Lodge. This coherer is in a circuit 
with a voltaic cell which operates a telegraph relay 
instrument; and this, in turn, is in a second circuit 
with a larger battery operating a recording apparatus 
and an electro-magnetic bell. The action of both trans- 



Marconi’s Coherer 


mitter and receiver was similar in principle to those of 
Popoff, but Marconi added a most valuable feature in 
providing a high vertical wire at the transmitting end 
of the line, whereas Popoff had used the high wire 
only at the receiving end. 

Another improvement introduced in the Marconi 
apparatus was two so-called choking-coils used in the 
first receiving circuit to prevent the waste of the 
electro-magnetic waves in parts of the apparatus 
where they are not a help to the action. The choking- 
coil is only a finely wound electro-magnet, which, 





















278 


ELECTRIC WAVES AND RAYS 


when in a circuit traversed by an alternating current, 
opposes to the passage of currents induced currents of 
the opposite kind, thus helping to confine the original 
current to certain parts of the circuit. 

. The theory by which the “snapping off” of electric 
waves into space is explained is an exceedingly com¬ 
plicated one, but the general idea we may give. 

It is supposed that as electric force is sent into the 
two sparking rods of the oscillator there are formed, 
in the space round about these rods, lines of electric 
force that are likened in shape to half hoops of spring 
steel. These hoop-like strains of electric force 
lengthen and flatten out in shape as more electric 
energy is conveyed to the rods and are thereby 
stretched, just as a spring of the same shape would be 
stretched if flattened. When the electric force in one 
rod has reached an intensity enabling it to leap the 
space from one ball to the other, overcoming the air- 
gap resistance, this strain is suddenly relieved. The 
flattened hoops of electric force then suddenly con¬ 
tract into circular form. But their ends of opposite 
polarity cannot pass one another, and as the portions 
of the curves furthest from the rod have contracted 
more slowly than these ends, the electric wave is 
“ snapped off ” from the rod in circular form, revolv¬ 
ing upon itself after the manner of a smoke ring, and 
so travels off into space, growing larger and larger 
just as a blown smoke-ring does. 

Following these lines of electric strain come other 
lines of magnetic strain, which, however, run round 
the rods instead of along their lengths. These mag- 
netic lines are said to be the result of the breaking of 
the electric lines of force, and they too reach their 


ELECTRIC WAVES AND RAYS 


279 


maximum, then collapse and are detached. These 
processes repeat themselves in rapid alternation until 
that one oscillation ceases. 

The rod is again charged, the strain grows, the 
spark passes; and the process is repeated with every 
charging and discharging of the rods. 

This description, derived from the Encyclopedia 
Americana, is meant only to give a very general idea 
of the production of electric oscillations, or waves, in 
wireless telegraphy. Now, as to the reception of 
these same waves. 

At the transmitting station stands a vertical wire. 
Theorists tell us that this may be considered as half 
of an oscillator, since the earth, a perfect conductor, 
takes the place of the other half and may be con¬ 
sidered as containing a second wire corresponding to 
the first, as if the first were reflected in a mirror hori¬ 
zontally below it. From this circumstance this 
theory is known as the “ reflecting ” theory. 

When waves going through space are intercepted 
by the vertical wire, we have a repetition of what 
takes place between the two rods of the oscillator. 
When the vertical wire is charged, lines of force are 
formed, as in the case of the rod of the oscillator, and in 
the same way are snapped off from it in waves that 
are propagated, it is believed, along the surface of the 
earth in concentric circles from the foot of the wire, 
following the contour of the surface. This theory 
explains why wireless telegraphy is not prevented 
from acting 1 even when hills occur between the 
stations, since the waves are supposed to follow the 
contour of the earth near the surface of the ground, 
or the sea. 


280 


ELECTRIC WAVES AND RAYS 


In the beginning of 1899 Marconi’s system had 
been used successfully to transmit messages across 
the English Channel. He had already in England 
secured the backing of the British Telegraph depart¬ 
ment, being helped especially by the hearty aid of 
Sir W. H. Preece, chief electrician to the Post-office. 
Beginning on Salisbury Plain, between 1896 and 1S98 
messages were sent across the Bristol Channel, then 
for a distance of sixteen miles, and between South 



Diagram of the Marconi Transmitter and Receiver 

At d are the spheres of the transmitter, connected, one to the “ exploring” wire V, 
the other to the ground, as well as by c c to the secondary of the induction coil I, the 
key K being connected with the primary. The coherer C is connected, one pole to the 
ground, the other to the exploring wire V 5 , and is also in circuit with the cell b and a 
relay actuating another circuit which works a trembler T, of which H is the hammer 
for decohering. When the waves pass from V 2 to the coherer the resistance drops by 
the coherence of the filings contained in the latter, and the current from b works the 
relay R, the “choking coils” a a between the coherer and the relay sending the waves 
through the coherer instead of the relay. The relay in turn causes the battery B to 
send its current through the tapper H and also through the recorder A. 


Foreland lighthouse and the lightship twelve miles 
away. 

To communicate across the channel he used a wire 
a hundred and fifty feet high and sent his messages 
thirty-two miles to a village on the French coast, two 
miles north of Boulogne. During the same year the 
system was tried successfully in the British Naval 
Maneuvres. Before the end of the year the signals 












































ELECTRIC WAVES AND RAYS 


281 


had been sent nearly a hundred miles. During this 
same year also Messrs. Poliak & Virlag adapted to 
wireless telegraphy the device of rapid transmission 
by means of a punched tape, as had already been done 
in so many forms of line telegraphy. 

Late in 1899 the New York Herald engaged 
Marconi to come to this country for the purpose of 
reporting the international Yacht Races from a vessel 
that should follow the yachts and telegraph wireless 
messages to a yacht in the harbor connected by a 
cable with the city. 

There were many experiments made during the 
year upon the availability of wireless telegraphy for 
signaling in the army or navy, but no final conclusion 
as to the best system was arrived at. The commercial 
progress made showed a continued rapid increase in 
the use of telephones, there being half a million sub¬ 
scribers ; other applications of the electric light to 
decorative purposes at the time of the Dewey Parade 
in New York; and the entering of the electric light 
companies into the enterprise of supplying power in 
storage batteries that could be charged by the light¬ 
ing plants, during those hours when their patrons did 
not call upon them for current. 

In this year also there was a decided disposition on 
the part of manufacturers to substitute motors for 
pulleys and belting in driving manufacturing machines, 
and the makers of such machines were compelled to 
recognize the public demand by adopting them 
especially for use with motors. The building of the 
two new warships, Kearsarge and Kentucky showed 
the approval of electricity as a power, for both 
were electrically equipped throughout. 


282 


ELECTRIC WAVES AND RAYS 


The great demand for copper wire largely increas¬ 
ing its price, the manufacturers of aluminium were 
enabled to enter into active competition, showing the 
beginning of the warfare between these two metals 
which Tesla had predicted. For city use storage bat¬ 
teries were much used in electro-automobiles, since 
the gasoline engine was not yet so far improved as to 
be a dangerous competitor. The progress of electrical 
railways may be briefly noted in the statement that 
by the end of 1899 there were nine hundred and fifty 
in the United States. 

The year 1900 was, in general, merely a time of 
further increase along the same lines, together with 
certain improvements in all directions. There were 
at the end of the year three and a half billions of dol¬ 
lars invested in electrical enterprises. The extending 
of cables and telegraph lines continued throughout the 
world, new territory being constantly equipped, and 
the field of the electrical railway also continued to ex¬ 
tend, being marked especially by the attempt to utilize 
the very much higher speed possible with electricity 
as a motive power. Among such devices was a plan 
for a mono-railroad on the “ Behr System,” — a road 
capable of making a hundred and ten miles an hour. 
Yet the motive power is said to be safely controlled by 
devices for switching the motive power into dynamos 
which apply brakes, and thus use the motive power it¬ 
self to check too great speed. 

The investigations as to the value of x-rays compre¬ 
hended their application as a means of fighting diseases 
coming from germs. The results in tuberculosis were 
not favorable, but in certain skin diseases, such as lupus 
especially, the therapeutic effects were excellent. 


ELECTEIO WAVES AND RAYS 


283 


Other rays than the x-rays had been discovered since, 
among them being the Becquerel rays, and these con¬ 
tinued to be investigated. The names of Professor 
Gauss and Professor Clerk Maxwell were in this year 
honored by the International Electric Congressat Paris, 
the “Gauss” and “Maxwell” being decided upon as 
the units respectively of magnetic field and magnetic 
flux. 

The nineteenth century ended with the entry of 
electricity into nearly all, if not all, the fields it has 
since occupied, and it hardly needed any great power 
of prophecy to foresee that as the force was more thor¬ 
oughly studied and even better means of application 
devised, it would be likely to supersede in the service 
of man nearly every other force or energy. In delicacy, 
in power, in portability, in neatness or in exactness of 
application, it had already demonstrated its power to 
rival nearly every other agency controllable by man. 
It was demonstrated beforehand that our own century, 
the twentieth, must be distinguished as the Age of 
Electricity, and the rapidity of human progress is cer¬ 
tain to be stimulated as never before by the possession of 
this agencv and the control of its manifestations as a 
means of detecting, of measuring, and of governing, 
the substances and forces of nature. 


CHAPTER XXII 
ELECTRICITY IX THE TWENTIETH CENTURY 


The year beginning the twentieth century was 
notable both practically and theoretically — that is, 
electricity was developed not only in business ways 
but as a science. As a business its growth aided what 
social philosophers call the “ centrifugal ” movement 
of the community ; it helped to counteract the tendency 
to gather in large groups —in cities. For the exten¬ 
sion of the telephone, the transmission of power by 
wire, and the lighting of small places, made business 
in smaller towns easier and more profitable, while 
living in remote places became more agreeable. 

The electric automobile in this year showed itself 
capable of high speed, covering a mile in sixty-three 
seconds ; and Edison, always quick to foresee electrical 
requirements, brought out an improved storage battery, 
the elements being nickel and iron. But though this 
form of cell is light and lasting, not injured by 
changes in conditions of use and simple in chemical 
action, the lead cell seems as yet to be preferred. 

The telephone or telegraph “switch-board ” has not 
yet been described. The theory of it is simple. Imag¬ 
ine six lines to enter an office. Suppose we fasten three 
of them parallel to a board; and then the other three, 
also parallel, cross them at right angles, but are on the 
back of the board. There is now no connection between 
them. Then we bore holes through the board where 
the wires would cross if they were on the same sur- 

284 


ELECTRICITY IN TWENTIETH CENTURY 285 


face. If now a plug of some conducting material be 
put into any of the holes, it will connect two, and only 
two of the wires, and each hole will connect a dif¬ 
ferent couple. Any two wires not in use already may 
be connected without interfering with any other two. 
The commercial switch-board in improved form is 
based on this principle, for telegraph and telephone 
lines and other purposes. 

The use of arc and incandescent lamps greatly in¬ 
creased, and a device for using only a small part of the 
current, or switching the current into large or small 
filaments or into one or two at a time as desired, was 
introduced, so that a lamp could be turned up or down. 

The Pan-American Fair at Buffalo surpassed all pre¬ 
vious attempts at electric illumination, the great suc¬ 
cess of the fair being its enormous electric tower in 
front of which was a cascade capable of the most mar¬ 
velous effects of lighting, by means of electric lights 
that threw prismatic hues into the waterfalls. The 
exhibition in the building devoted to the arts dependent 
on electricity was declared to be the finest ever held. 

An important step in electro chemistry was the im¬ 
provement of the process of producing nitrogen com¬ 
pounds bj T bringing about the union of nitrogen and 
oxygen in the presence of electric arcs. As the nitro¬ 
gen of the atmosphere is inexhaustible, and as soils 
are exhausted mainly by the removal of nitrogen and 
its compounds, there is hardly any process more im¬ 
portant to the life of mankind than methods of sepa¬ 
rating the nitrogen of the atmosphere readily and 
cheaply. If this could be done, nitrogen could be put 
back into the coil, and the food problem would be 
solved, so far as productiveness is concerned. 


286 ELECTRICITY IN TWENTIETH CENTURY 


In this year also, Professor Pupin, of Columbia Col¬ 
lege, a pupil of the German von Helmholtz, sold to the 
Bell Telephone Company his devices for an electrical 
relay for increasing the distance submarine cables would 
transmit the telephone vibrations. Essentially the in¬ 
vention consisted in introducing induction coils in the 
cable, so as to strengthen the vibrations. 

The progress in wireless telegraphy continued, most 
of the transatlantic liners adopting the apparatus, and 
a station being installed out at sea upon the Nantucket 
Lightship. A new era, too, was promised by the inven¬ 
tor Marconi who on December 12, 1901, received sig¬ 
nals across the Atlantic Ocean. Landing at St. Johns, 
Newfoundland, on December 6th, with two assist¬ 
ants, Marconi prepared his apparatus. On the 10th he 
sent up a kite and then a balloon to raise the vertical 

wires but both were carried away. On the 12th a kite 

*/ 

was raised about 400 feet, and all was ready to receive 
signals. Marconi had arranged that the “ S ” of the 
telegraph alphabet (. . .) should be sent at certain 
intervals every day at a fixed time, from Poldhu, 
Cornwall, England ; and about half past twelve, the 
signals came — the three clicks were heard by means 
of a telephone-receiver. 

A full and striking account of the occurrence was 
written by Ray Stannard Baker in McClure's Maga¬ 
zine for February, 1902. This article also explains the 
Marconi system, including the method of “ tuning ” a re¬ 
ceiver to respond only to waves of a certain number of 
vibrations a second ; and also calls attention to the com¬ 
parative cheapness of transatlantic wireless telegraphy 
as compared with the cable — the wireless stations cost¬ 
ing only one-twelfth the amount necessary to lay a cable, 


ELECTRICITY IN TWENTIETH CENTURY 287 


and the maintenance being incomparably cheaper. 
Though the article concludes with a suggestion that the 
cables may soon be made useless, that prophecy is 
hardly likely to be fulfilled. As the telegraph still finds 
uses despite the telephone, the cables will hardly be en¬ 
tirely superseded by the wireless. 

The same development continued in 1902, the gen¬ 
eral increase being estimated at twenty per cent, over 
1901. Following the example at Niagara, a company 
was organized to furnish 5,000 horse-power from the 
Sault Ste. Marie. In wireless telegraphy Marconi suc¬ 
ceeded in transmitting a sentence across the Atlantic, 
while another system than his — the De Forest — was 
used in the United States Naval Maneuvres. In this 
system, instead of the coherer used in the earliest ex¬ 
periments of Marconi and others, the device for receiv¬ 
ing the electrical waves is what is known as an “ anti¬ 
coherer.” Two plugs of tin are inserted in a tube and 
between them is glycerine containing lead oxide. This 
forms an electrolytic device which causes particles of 
tin to be conveyed between electrodes ; but the electric 
waves act as interrupters of this action, and they in¬ 
crease the resistance of the circuit and cause disturb¬ 
ance that is heard by a telephone. The waves close 
the circuit in the coherer tube, and interrupt it in the 
anticoherer tube; but in either case the telephone or 
other device responds to the change of condition, and 
thus signals can be read. 

There are other devices used for the same purpose, 
but only a brief explanation of them can be given. 
Marconi used for a time the Castelli coherer, in which 
a drop of mercury replaced iron filings, and acted as 
they did, to close more completely the gap between 


288 ELECTRICITY IN TWENTIETH CENTURY 

the conductors on the ends of the tube ; but in his 
transatlantic experiments he used an “ autocoherer ” 
or magnetic detector, which was practically an induc¬ 
tion coil, except that instead of the core of wires there 
was an endless wire rope running through the inner 
coil endwise. As this rope moved it touched the 
poles of two magnets. This made it change slowly in 
magnetism as parts of the rope approached and receded 
from the magnets. The electrical waves from the dis¬ 
tant station change the electrical condition of the outer 
coil; this induces changes in the inner coil, and thus 
the magnetism of the rope is affected. To recognize 
these changes a telephone receiver is in circuit with 
the outer coil, and in this clicks are heard as the mag¬ 
netism is changed. Such is the explanation given by 
William Maver, Jr., in an article reprinted from 
Cassier's Magazine in the Smithsonian Report for 
190L 

It will be seen that many delicate means for 
detecting variations in electrical conductivity have 
been successfully used in wireless-telegraph receivers. 
The “ barretter,” for example, is based on the princi¬ 
ple that a current heats a conductor, and this increases 
resistance. The telephone, as before, is used for mak¬ 
ing the results of the resistance audible. 

It is a significant proof of the ability and ingenuity 
of scientific workers in the electrical arts that already 
there is a long list of systems of wireless telegraphy, 
and many rival inventors claiming credit for the various 
devices. The essential features of the art have, how¬ 
ever, been here set forth ; namely, the creation of 
electrical oscillations by coils, condensers, or dynamos, 
their reception in such a way as to change the con- 


ELECTRICITY IN TWENTIETH CENTURY 289 


dition of an electrical current, and the perception of 
these changes by telephone or mechanical devices. 
But the main use of the system at present is for 
communication at sea. 

Other improvements in telegraphy continued. A 
Pacific cable was laid — the longest in the world. The 
telautograph was adopted in this year by the United 
States War Department. This device, invented a 
number of years before, and exhibited at the Chicago 



The Telautograph 

The upper plate represents the transmitter, 
the lower the receiving instrument. 

Fair in 1893, consists essentially of mechanical appara¬ 
tus so contrived that the motions of a writing instru¬ 
ment at one end of a line are repeated at the other, 
giving a facsimile of drawing or handwriting. 

To understand this instrument, invented by Elisha- 
Gray, it must be remembered that any dot on a piece 
of paper can be reached if we are allowed to move in 
only two directions. Thus to reach the centre of the 









200 ELECTRICITY IN TWENTIETH CENTURY 


page we have only to move upward or downward un¬ 
til opposite the centre, and then either right or left un¬ 
til the centre is reached. Now if we connect a pen 
with two telegraph wires, one of which responds to 
vertical and the other to horizontal motions we can 
cause these lines to move another pen both vertically 
and horizontally — that is, up and down or to and fro 
on the sheet of paper. The pen is.attached to a rod 
that moves two plates so as to increase and decrease 
the resistance in the two wires by sliding these plates 
across a row of bars, including more or less of them in 
the line. 

At the receiving station are two electro magnets 
that are strengthened or weakened in accordance 
with the current of the lines, and these move a pen 
that follows the motion of the sender’s pen. 

Another facsimile telegraph uses the received cur¬ 
rents to move a mirror that reflects a ray of light on a 
slip of photographic paper, and thus records the 
motion of the pen in a photograph. Still a third 
form of facsimile telegraphy uses two cylinders, re¬ 
volved at the same rate, at two distant stations. The 
paper upon one cylinder is marked whenever a current 
passes. The other cylinder has the message written 
in insulating ink on tin foil (a conductor). Upon the 
sending cylinder rests a point as the cylinder turns, 
and, being moved slowly along, touches each part of 
the cylinder surface in turn, following a spiral path. 
Whenever there is a written character, the current is 
interrupted by the insulating ink, and this lets the 
pencil at the receiving station make a mark on the 
receiving cylinder. Thus the whole message or 
design is gradually traced on the paper. A modifica- 


ELECTRICITY IN TWENTIETH CENTURY 291 


tion of this method moves the sending point to and 
fro over a fiat surface, but the principle is the same. 
Neither system is rapid, and neither is in extended 
use. 

The history of the year 1902 in regard to commercial 
electrical arts records the progressive use of electricity 
in all fields so rapidly that only general statements 
can be made. American engineers began to find 
employment in all parts of the world, and the use of 
electricity for light power and traction ceased to be 
notable only because it was an every-day matter. 
Russia, Switzerland, Alaska, appear as fields for elec¬ 
trical enterprise, while the older established systems 
are enlarged, improved, and developed. Marconi 
had established thirty-seven stations by the end of 
1902, and practically all great steamers carried wire¬ 
less apparatus. In cities there were single buildings 
using 1,000 horse-power, and the railways had either 
adopted or were studying electrical methods of pro¬ 
pulsion. In this latter field, traction, the use of the 
direct current for motors began to be laid aside in 
favor of alternating-currents, for the reason that the 
latter were better adapted to long distances and heavy 
traffic. 

The advantages of the alternating currents consist in 
the readiness by which they may be transformed in fre¬ 
quency and thus transmitted, and then retransformed 
into any condition desired for use. They may be trans¬ 
mitted at low voltage, and then increased to high 
voltage ; or transmitted as alternating and then com¬ 
muted or transformed into direct current. The direct 
current requires heavy conductors, which are expen¬ 
sive, and so makes a number of power-stations neces- 


292 ELECTRICITY IN TWENTIETH CENTURY 


sary. But these are engineering questions, and prin¬ 
cipally concern experts. The same remark will apply 
also to the questions of the use of the various phases 
of current for different purposes. And as to these 
latter years in the genealogy of “ Father Amber,” we 
must perforce admit that the branches of the family 
have grown to numbers and varieties that would re¬ 
quire a library for their discussion. The individuals 
we cannot know, but must content ourselves with 
assigning each to its branch. 

A glance over the field will help us to understand 
at least something of its subdivisions. To begin, there 
is first the theory of electricity — its nature, its 
origin, and its laws; and this raises the entire ques¬ 
tions of matter, energy and life. Then comes the 
generation of electricity, by all methods — friction, 
light, heat, chemical action, magnetic fields, radiant 
matter. Thereafter we take up its applications to 
mechanics, to chemistry, to lighting, heating; and 
each of these gives rise to a whole art, and every art 
to its own great classes of machines, tools, and 
apparatus. 

The amateur may know the general principles that 
underlie them all; he may know the particulars of a 
branch or two — but for the rest he must rely upon 
the technical books after he has acquired enough com¬ 
mand of the terms to follow the printed explanations. 
The days of universal knowledge in one head are 
long past. 

Passing over, therefore, the general statements 
showing the inevitable commercial progress in the 
various arts, and making no attempt to describe 
further the modifications of apparatus for wireless 


ELECTRICITY IK TWENTIETH CENTURY 293 


telegraphy — many of which were directed toward 
removing the serious objection to the system, that its 
messages might be intercepted or interrupted, and 
were not secret—we will mention as significant 
events of the year the attempt to communicate by 
wireless waves with submarine vessels. 

Experiments showed that the waves could not be 
depended upon to extend their influence further down¬ 
ward into the sea than rays of light would reach. 
Whether this was due to the supposed identity of the 
two forms of action or was a mere coincidence was 



The Cooper-Hewitt Mercury Vapor Lamp 


not certain. The deadening effect of the water 
undoubtedly tended to make the vibrations slower 
and slower until they became too weak to affect the 
receiving apparatus. 

Two new forms of electric lighting were brought to 
public notice in this year, the Cooper-Hewitt mercury 
light and the light known as the mercury arc, in¬ 
vented by Dr. Arons and Professor Steinmetz of Ger- 







294 ELECTRICITY IN TWENTIETH CENTURY 


many. The Hewitt light, though cheap and brilliant, 
was open to the serious objection of its color, which, 
lacking the red rays, was unpleasant to the e} T e. This 
defect, however, does not affect its use for decorative 
purposes and for photography, the latter being a very 
favorable ffeld, since the red rays are the least actinic 
and least valuable in photography. 

The curative effect of the vibrations coming from 
electric lights of varying intensity was successfully 
applied by Dr. Finsen, of Denmark, who received one 
of the Nobel prizes in recognition of his researches and 
practice. Roentgen also had been the recipient of 
one of these ten-thousand dollar prizes a year or two 
before. Professor Bedell, of Cornell, found that 
direct and alternating currents could be transmitted 
simultaneously over the same wire without interference, 
a discovery that promised, like most recent discoveries 
in the field of electricity, a wide development. 

In fact, after the summary of the year’s progress in 
general lines, the compiler of the electrical portion of 
the Journal Almanac remarks : “ All the discoveries 

mentioned have an important bearing upon every 
possible use of electricity” — a sentence which is 
gratefully adopted as being a most succinct expression 
of the state of mind produced in one attempting to 
foresee the bearing of recent researches upon future 
electrical arts. 

As illustrating the difficulty of guarding wireless 
telegraphic messages against interference, an amusing 
anecdote is quoted from an English source. Professor 
Fleming, an electrical engineer, had declared in a 
lecture that there was no interference of the waves. 
Four months later, while demonstrating the Marconi 


ELECTRICITY IN TWENTIETH CENTURY 295 


system before the British Institution, he found the 
messages sent from the Poldhu Marconi station sud¬ 
denly thrown into confusion. Professor Fleming, like 
a true Briton, wrote to The Times complaining of 
the interference, and was replied to by Professor 
Maskelyne, the scientific expert, who confessed that he 
had been tempted to make this practical answer to 
Professor Fleming’s claim that the messages could not 
be interfered with. 

He also pointed out that Fleming had claimed to use 
a tuned set of vibrations, and that he had been able to 
interrupt these by means of an untuned transmitter. 

The year 1904 was notable for the general increase 
in the size and force of apparatus, machines of enor¬ 
mous capacity being practically used. The wireless 
telegraphy development was slow, and the United 
States Government remained undecided between rival 
systems. In atmospheric electricity investigations were 
followed up in the hope that by means of waves 
thrown into the air clouds or fogs could be condensed 
and rain precipitated. 

In telephony the greatest improvement was the in¬ 
troduction of the automatic system of making connec¬ 
tions between subscribers. The general principle under¬ 
lying the very complicated apparatus that enables a 
subscriber to connect with a desired number bears 
some likeness to the principle underlying the telauto¬ 
graph. Just as in that apparatus the pencil can be 
made to touch a particular point by means of two 
motions, so the connection of a telephone can be made 
by a rotating dial to travel in various directions so as 
to rest upon a given point. 

Suppose a table of numbers to be arranged upon a 


296 ELECTRICITY IN TWENTIETH CENTURY 


large sheet, and at each number the connection with a 
line wire to be placed. To reach any one of these lines 
a device is adopted causing the connecting piece to 
travel vertically a certain number of steps and then 
horizontally along a line of numbers until it reaches 
the desired point. 

In Professor Houston’s book, “ Electricity in Every¬ 
day Life,” encyclopedic as it is, he declares these 
systems too complex to be described in the space at 
his command. A brief description of the apparatus 
may however be given. 

Suppose a subscriber wishes to call 983. On his 
telephone is a dial containing the numbers from one to 
nine and then a cipher. Placing his finger in the 
hole marked nine, he turns the dial until it stops 
and then releases it. This causes a connection with 
the group of numbers beginning with 900. He then 
places his finger in the number eight, turns the dial as 
before, and by its return is connected with the 980 
group. A similar action gives him the number three 
and its group, whereupon he presses a button that 
rings the bell of receiver 983. 

The effect of turning the dial upon the subscriber’s 
telephone is to send to the central exchange as many 
electrical impulses as the number he has touched. 
Thus, if he begins by putting his finger in the hole 
number nine, and turns the dial until it stops, and 
then lets go, the dial in returning to its place makes 
nine electrical connections and sends nine impulses of 
current to the central exchange. 

Each of these impulses at the exchange raises a rod a 
single step upward. Upon this rod is a projection 
which by each step upward is brought opposite to a dif- 


ELECTRICITY IN TWENTIETH CENTURY 297 


ferent range of metal rods. The first range contains the 
numbers up to ten, the second up to twenty, and soon. 
The second number touched turns the rod sideways 
or twists it, causing the projection to travel horizontally 
along the line of rods until it reaches the number 
desired. In the case supposed above, number eight. 
Now, if this last rod be divided into nine portions, 
a third movement, also upward, may be made to 
connect the subscriber’s line with any portion of this 
rod. 

The above description is not meant to be an exact 
statement of what occurs, but only shows the general 
principles. 

In electro-chemistry there was notable progress as 
the importance of improved apparatus was shown, the 
many experiments made commercially enabling en¬ 
gineers to get better results by better designed appara¬ 
tus— the electric furnace, for example. 

In electric traction the advantages of using alter¬ 
nating currents, which could be transmitted over a 
small wire, tended to displace the third rail system of 
traction in certain places, since the advantage of using 
the third rail lay largely in its great capacity for direct 
current. The Subway in New York City, however, 
preferred the direct current, and was opened in Octo¬ 
ber of 1904 with motor cars, each supplied with four 
motors of two hundred horse-power. An alternating 
current locomotive designed by Ward Leonard was 
successfully tested in Switzerland this year. The ad¬ 
vantages of the alternating current comprise a quicker 
acceleration and therefore ability to handle heavier 
roads. Undoubtedly, however, in the development of 
the art the field will be divided between the two forms 


298 ELECTKICITY IN TWENTIETH CENTUKY 


of current in accordance with their special adaptability 
to particular needs. 

The year 1905 saw an advance in electric lighting 
due to the employment of certain of the rarer ele¬ 
ments the qualities of which adapted them especially to 
incandescent lighting. From one pound of tantalum^ 
for instance, it is possible to construct twenty thousand 
lamps, and these have the great advantage that 
tantalum increases its resistance with increasing 
temperature, and, as it were, controls the lighting of 
itself. The stronger the current, the more the resist¬ 
ance ; the weaker the current, the more of it passes ; 
which results in a steady light. Other substances also 
are used, osmium, for example, each with advantages 
of its own. 

A union that promises most important results in the 
production of power is that of the steam turbine-engine 
with dynamos. The turbine engines require but little 
floor space, and have an evenness of motion that makes 
them specially desirable for the dynamos that must be 
run at an even speed in order to produce currents of 
an even phase. 

In telegraphy, the Barclay Typewriter System used 
typewriters at each end of the line, both for trans¬ 
mitting and receiving. This enabled the operator to 
make a typewritten original, and at the same time to 
have the message transmitted to a distant office and 
there taken down automatically by another typewriter. 
The putting together of the telegraph and the type¬ 
writer was not a remarkable achievement theoreticalljq 
but was a proof of mechanical ingenuity and of the 
certainty with which electrical mechanism could be 
made to act. 


ELECTRICITY IN TWENTIETH CENTURY 299 


In brief, the principle was to cause the transmitting 
keys to transmit their motion to electro-magnets, each 
key operating a single magnet depressing the receiv¬ 
ing typewriter key corresponding to the letter sent. 
The method of effecting this is very complex, but in 
general is similar to the device used for operating the 
printing wheel of a stock-ticker. A very excellent 
description of the system is given in the Encyclopedia 
Americana in the article “ Telegraphy,” where like¬ 
wise all the modern systems are well described. An¬ 
other equally clever device of similar nature causes 
the sending of the Morse signals to operate a machine 
that prints the message in ordinary letters. 


CHAPTER XXIII 
THE PRESENT AXD THE FUTURE 

The author is almost tempted to make again the 
well worn excuse of the size of his subject, and he re¬ 
peats it only as a warning that in speaking of the 
future not much that is definite can be said. From 
the authorities on the subject, however, certain con¬ 
clusions may be adopted. 

First, upon the improvement of electrical ma¬ 
chinery. 

It seems that there is very little margin for increas¬ 
ing the mere mechanical value of motors and dyna¬ 
mos. The present best device save certainly some¬ 
thing more than nine-tenths of the energy that, theo¬ 
retically, they should yield ; consequently, improve¬ 
ments bringing out more than the extra tenth are im¬ 
possible. 

As regards batteries, there is no theoretical reason 
why the efficiency of storage batteries in proportion to 
their weight and durability should not be greatly in¬ 
creased. But this improvement might bring other 
disadvantages in regard to the rate at which power 
could be discharged. Upon the improvement of stor¬ 
age batteries rests the future of electric automobiles. 
As to the direct battery, the great problem of the 
future is to find some means of using the energy 
stored up in coal. Unless a battery using coal can be 
made, into which coal can be fed as readily as into a 

300 



The “Bullock” Generator (3,500 kilowatts) and “ Allis-Chalmers, 
5,000 Horse-Power Engine, World’s Fair, St. Louis, U. S. A. 

Frotn stereograph, copyright by Undenvood and Underwood , N. V. 


















THE PRESENT AND THE FUTURE 301 


fire, the prospects for the coal battery are not bright. 
The problem is being worked upon by many in¬ 
ventors. 

Another desirable achievement is the production 
of light without heat, for at present the greater part 
of the energy used in lighting goes into heat and 
therefore is wasted. In this case the margin for im¬ 
provement is great, since the loss of energy when 
turned into light varies from ninety-eight per cent, to 
about ninety. 

In regard to the application of electricity to the 
solving of mechanical problems we can only suggest 
that there is no mechanical motion to which elec¬ 
tricity cannot be applied, and therefore we may ex¬ 
pect the field continually to enlarge. The cheaper 
production of electricity from natural powers will 
make its use more general in all fields of in¬ 
dustry. 

A recent discovery announced by Nikola Tesla dur¬ 
ing the year is that the capacity of conductors varies 
according to a number of conditions and cannot be 
considered as constant. He finds that the degree of 
elevation above the ground, the season of the year, 
the time of day, have a by no means small effect upon 
the capacity of conductors. And he points out that 
some of the laws he has discovered may enable us to 
make instruments that will register, for instance, the 
altitude of places and some of the other particulars 
that vary the capacity of conductors. These varia¬ 
tions of capacity may become theoretically im¬ 
portant. 

The improvement of the telegraph has been enor¬ 
mous during its shortlifetime, but it is not yet possible 


302 THE PRESENT AND THE FUTURE 


to accomplish completely two desired ends. One is 
the sending of telegrams with great rapidity during 
the hours when they are most numerous without the 
need of employing an apparatus which is too expensive 
for the transmission of the average number of mes¬ 
sages during the whole twenty-four hours. 

In the telephone— while wireless telephony is pos¬ 
sible, it is by no means well advanced. There is ap¬ 
parently no impossibility in achieving the telephoning 
by tuned waves, so that one person can communicate 
with another regardless of locality. This result is of 
course far in the future. 

A recent invention, the “ telegraphone,” enables the 
owner of a telephone to have any message that may 
be spoken into his receiver recorded in such form that 
lie can repeat it exactly as it was transmitted in his 
absence. The same principle that records the tele¬ 
phone vibrations has also, I believe, been used to 
record telegraphic messages. 

It consists of a wire of mild steel arranged so that 
the movement of a telephone receiver’s diaphragm 
impresses upon the steel varying amounts of mag¬ 
netism— the amounts depending upon the nearness of 
approach of the diaphragm of the telephone. The 
wire is caused to pass from one winding reel to an¬ 
other close to the vibrating diaphragm, and receives 
magnetic impressions that persist for a considerable 
time ; exactly how long I do not know. 

Upon reversing the motion of the coils the mag¬ 
netization of different parts of the wire attracts the 
telephone receiver diaphragm, so that its motion is re¬ 
produced, the vibrations that made the magnetic forces 
are repeated, and the telephone repeats the message. 


THE PRESENT AND THE FUTURE 303 


It is evident that the strength of these magnetic 
impressions could easily be increased by using a small 
permanent magnet to be moved by the diaphragm, 
and very likely this is done by the inventor. In a 
word, the invention is a “ recording-telephone ” that 
translates its diaphragm movements into varying mag¬ 
netic fields in the wire, and so the telephone repeats 
the message. 

The transmitting of pictures by telegraph is yet 
in its infancy. The method of sending designs a 
point at a time is much too slow. The methods of 
transmitting the points to a large surface simulta¬ 
neously require far too many wires, and yet it is too 
early to be certain that a photograph of a reflected 
scene will not one day be transmitted by multiple cur¬ 
rent over a single wire. 

As regards wireless telegraphy, we have already 
pointed out that the much desired improvements are in 
securing secrecy of messages, preventing interference 
with transmitted waves, and extending the space cov¬ 
ered. The use of electricity in recording and report¬ 
ing weather is already wide-spread, but it is possible 
that the future will give us methods by which we may 
to some extent control the weather, by causing moisture 
to be gathered into drops, and to fall in rain, at least 
over a limited area. 

In the application of electrical power there are 
many fields yet unfilled. Charles Wilson Price in a 
recent article points out that portable electric power 
upon self-driven engines should be available for brief 
times and in remote districts ; and of course the ap¬ 
plication of electricity to airships is eminently de¬ 
sirable. Electro-chemistry is one of the youngest of 


304 THE PRESENT AND THE FUTURE 


our sciences and will be sure to advance directly 
in proportion to the cheapening of electrical power 
and its better application in the form of heat and 
other manifestations. The reign of the steam loco¬ 
motive has lasted only about seventy-five years, and 
we are at the very infancy of electrical traction. It 
is therefore not unreasonable to expect the greatest 
practical developments in this field. Engineers pre¬ 
dict the use of high tension currents transformed by 
apparatus carried on tlie locomotives themselves , as a 
solution of electric traction problems. 

The life of electrical machinery compares most 
favorably with that of machines dependent upon 
steam-power. Not only do the electrical appliances 
last longer, but they are worth more as material after 
their active life is finished. As to the capability of 
applying natural forces to electricity, the field has 
hardly yet been entered except in the case of a few of 
our greatest rivers and waterfalls. It is not unreason¬ 
able to expect not only the use of water power every¬ 
where, but the harnessing of the wind and, at a more 
distant date, perhaps the direct conversion of sunlight 
into the slower vibrations useful in electrical ma¬ 
chinery. As to the transmission of power, engineers 
at present believe that there is a practical limit to its 
distance, since in order to extend the length of lines * 
'we must increase the tension of currents and thus ap¬ 
proach the limits of economical insulation. 

It is believed that there is no impossibility in secur¬ 
ing enormously high speeds in electrically driven rail¬ 
ways. In theory they are entirely possible, and the 
dangers and difficulties of high speed traction can un¬ 
doubtedly be met by the ingenuity of inventors, since 


THE PRESENT AND THE FUTURE 305 


the motors employ the same energy for control as for 
motive power. 

The subject of wireless telegraphy has already been 
rather fully treated in proportion; but the future will 
see a great advance in all directions, and we may hope 
for the novelties of wireless transmission in the ap¬ 
plication of the waves to other uses than that of con¬ 
veying intelligence — as foreshadowed by Tesla’s 
“ telautomaton,” and in various projects for control¬ 
ling aerial craft, exploding distant magazines, and 
so on. 

As regards the questions relating to radium and 
similar radio-active substances, they can hardly be 
considered to come within the scope of a book on 
electricity, although the methods of electrical science 
must be used in studying atomic activity. The possi¬ 
bility of using the rays given off either primarily or 
secondarily, by various substances, to affect electrical 
devices by charging or discharging conductors, and so 
on, opens up a field wherein much speculation is pos¬ 
sible ; but it has not yet been particularly developed. 
The possibilities resulting from the study of radio¬ 
activity may include some method that will free man¬ 
kind from their present slavery to coal as a cheap 
means of securing energy; but the experiments so far 
made have been merely minute laboratory proofs, or 
possibly only evidences, that the energy locked up in 
atoms may under certain circumstances be set free. 

The telephone has opened to us one of the most 
promising fields of electrical science, but this has been 
evident from the general discussion of the subject al¬ 
ready given. The instrument has led to a renewed 
study of the whole field of sound vibration and its 


306 THE PRESENT AND THE FUTURE 


mastery. One of the most recent developments 
springing directly from the study of sound in connec¬ 
tion with electricity is the new musical instrument in¬ 
vented by Dr. Cahill, of Holyoke, Massachusetts. In 
essence this invention uses a piano keyboard for the 
purpose of bringing to bear upon telephone lines all 
the power of electrical alternators, that is, machines 
producing alternate currents of any desired rapidity 
within certain broad limits. Electrical vibrations are 
produced directly by electrical action, and hence are 
free from the imperfection due to the material of in¬ 
struments. Any character of musical tone may be 
thus exactly imitated, and when these tones are com¬ 
bined the resulting musical notes may be transmitted 
over anv number of circuits, and turned into audible 
vibrations of the air. 

The original machines cost enormously, one of the 
first built being worth two hundred thousand dollars 
and weighing two hundred tons. It is intended to 
establish a central station in New York to supply four 
or five thousand subscribers. 

In order to point out remarkable applications pos¬ 
sible in telephoning, we quote from a current maga¬ 
zine the statement that in Norway a hermetically 
sealed box is lowered into the water and contains a 
microphone. By means of a telephone sounds are 
heard from the submerged box, and these sounds 
differ according to the sort of fish approaching it, and 
the volume of sound gives a hint of the number of 
fish within hearing distance. 

As we read the current news we shall see daily 

1/ 

some new application of electrical devices. Thus, 
collected at random, I have before me items relating 


THE PRESENT AND THE FUTURE 307 


to the steering of ships, to the supplying of oxygen to 
divers at great depths, depths from which they are 
hauled by an electric motor, an electrical method for 
testing the purity of mineral water by its differing 
resistance to the passage of currents. Next comes 
an account of the instruments of the weather serv¬ 
ice, wherein electricity plays by far the most 
prominent part. Following this we have a long 
article describing a delicate device for detecting the 
electrical condition of the human nerves in invalids, 
as a preliminary to treating them therapeutically by 
an electric current. The next article describes and 
pictures a great floating dock at Rotterdam, the 
entire operation of which—pumping of water, pro¬ 
pulsion of the floating dock and the lighting of it — 
being done by electric devices. Another item tells 
how flour may be bleached by passing it through a 
high-voltage continuous-current arc. This is followed 
by a prophecy that household drudgery will become a 
thing of the past, owing to the numerous applications 
of heat, light, and power in the households supplied 
with electric current. There is even an apparently 
serious item describing a French invention by which 
mosquitoes or flies may be destroyed when alighting 
upon electrically charged wires; and from a recent 
scientific paper we have a description of an electro¬ 
magnetic gun, designed to propel projectiles by means 
of coils of wire successively brought into circuit with 
a battery. 

Strangely enough, I find with this an old newspaper 
clipping, taken at random from a scrap-book, describ¬ 
ing the same invention. Unfortunately this scrap is 
not dated, but it is certainly a number of years earlier 


308 THE PRESENT AND THE FUTURE 


than the invention described in The Scientific Ameri¬ 
can of October 20, 1906. 

From the same paper, a week later, comes an 
account of a motor designed to be run by electricity 
derived from the air or from thunder-clouds. As the 
ordinary motor is a dynamo reversed, so this invention 
may be described as a glass disk electric machine, 
multiplied and adapted to be run by electricity, 
instead of producing it. When this motor was con¬ 
nected with a vertical wire extending perhaps fifty feet 
into the air, it was found to rotate for some time 
before the occurrence of a storm. 

A few more clippings are devoted to the study of 
electricity as contained in growing plants and to the 
culture of fruits by enveloping trees in electric light 
and applying currents to the roots. And we may end 
this unsystematic collection by referring to a recent 
item warning bee-keepers against allowing their hives 
to remain within the light of electric lamps at night, 
as one keeper of bees declared that his eager little 
workers refused to stop so long as the light was shin¬ 
ing and literally worked themselves to death ! 

Undoubtedly the statements in some of these cur¬ 
rent accounts and anecdotes may be more or less dis¬ 
torted and exaggerated, but at least they will serve to 
show that there is no field of life in which we may not 
be met with some form of this omnipresent energy. 

Any attempt to trace the history of this great 
science must be inadequate, but we have at least 
within brief compass caused the reader to traverse 
the whole story of the discovery, the investigation, 
and the application of electricity from the bit of rubbed 


THE PRESENT AND THE FUTURE 300 


amber to the inquiry into the ultimate form of the 
atoms that make up matter. We have seen 
ignorant wonder and superstition pass through un¬ 
systematic to systematic study, and from uncertain 
theories to demonstration and practical proof that 
man can control the greatest of earthly forces. We 
have seen how the work of each investigator made 
easier the achievements of those who followed him, 
and have learned how what was a plaything of the 
curious has become the greatest agency within the 
command of mankind. 

Among certain Buddhist philosophers there was an 
idea that greater power is entrusted to the individual, 
and to mankind in general, in direct proportion to 
the growth of spirituality — the ability to make right 
use of the power granted. 

If this be true, the domain entrusted to man in the 
gift of the control over electrical energy is the most 
significant and the greatest in the history of mankind. 
It widens beyond our imagination the outlook of the 
race, and makes us dream of extending man’s domain 
even beyond this earth itself. 


FINIS 






Index 


Abbott, Edward, 25 
Acheson, E. G., 250 
Adams, J., 130 
iEsop, 12 
Ajax, Oileiis, 4 
Albertus, Magnus, 23 
Alector, 11 
Alglave, 169, 220 
Alston, Washington, 100 
Amber, 11, 12, 13, 28, 32, 42, 
103, 292, 309 
Amperage, 90 

Ampere, 74, 75, 78, 81, 82, 86, 
87, 90, 100, 106 

Ampere’s solenoid or coil (Illus¬ 
tration), 78 
Anions, 111 
Anode, 111 
Antony, 18 

Arago, 76, 77, 78, 86, 87 
Archereau, 143 
Arc-light, 69 
Argonauts, 7 
Aristophanes, 9 
Aristotle, 8, 12, 13 
Arons, Prof., 244, 293 
Athena, 4 

Atkinson, Philip, 135, 219 
Atlantic Cable, original (Illus¬ 
tration), 166 
Augustus, 7 
Aurelius, Marcus, 5 
Aurora Borealis, 8 

Babylonians, 3 
Bacon, Francis, 19, 20, 23, 25 
Bacon, Roger, 20, 23 
Bain, 148, 164 
Baker, Ray Stannard, 286 
Bakewell, 150 
Barclay, 298 
Barlow, Peter, 88,104 
Barlow’s invention (Illustration), 
89 


Beaton, J. A., 221 
Beccaria, 48, 51 
Becquerel, 91, 283 
Bedell, Prof., 294 
Behr, 282 

Bell, Alexander Graham, 205, 
206, 207, 212, 243, 254 
Bell Telephone (Illustration), 207 
Benjamin, Park, 12, 35 
Berliner, 212, 213, 243 
Bessemer, 125 
Blake, 214, 215 

Blake transmitter (Illustration), 
215 

Blossom, Levi, 168 
Boulard, 169, 220 
Bourseul, Charles, 160, 175 
Bowker, 232 

Boyle, Sir Robert, 30, 31, 32, 43 
Boze, 38 

Branly, Prof., 236, 237, 253, 270 
Breguet, 133 
Brett, Jacob, 151 
Bridge Duplex Telegraphy, dia¬ 
gram, 198 

Browne, Sir Thomas, 27 
Brugnatelli, 70, 125 
Bruno, Giordano, 19 
Bubble telegraph, 99 
Buchanan, President James, 167 
Buckingham, Charles M., 240 
BufFon, 48 

Bunsen, 128, 129, 168, 266 
Byrn, 100 

Cable, eirst submarine, 153 
Cabot, Sebastian, 16 
Caesar, Julius, 9 
Cahill, Dr., 306 
Canton, John, 49, 50, 51 
Canton’s Electric Chime (Ulus* 
tration), 50 
Carbon voltaic arc, 69 
Carbons, 69 


311 


312 


INDEX 


Carborundum Furnace (Illustra¬ 
tion), 250 
Carlisle, 09, 110 
Carpue, 7o 
Cassier, 288 
Castelli, 287 
Castor and Pollux, 7 
Cavallo, 40 

Cavendish, Henry, 52, 54, 178 
Cazal, 179 

Cervera, Admiral, 268 
Chaldeans, 3 
Chandler, A. B., 263 
Channing, 155 
Charles II, 34 
Christie, 197 
Clark, Latimer, 178 
Clarke, 107, 152 
Claudian, 15 
Cleopatra, 18 

Columbus, Christopher, 16 
Commutators, 104, 105, 106 
Commutators (Diagram of Two 
Part), 106 
Condensers, 55 
Conduction, 36, 38 
Conductor, lightning-rod, 46 
Conductors, non and prime, 35, 
38, 41 

Conington, 7 

Cooke and Wheatstones Instru¬ 
ment (Illustration), 122 
Cooke, William, 116, 122, 123 
Cooper, 130 
Cooper-Hewitt, 244 
Cooper-Hewitt Mercury Vapor 
Lamp (Illustration), 293 
Copernicus, 20 
Copley, 90 
Coulomb, 54, 55 
Coulomb, 90 
Cowles, 251 
Cowper, William, 127 
Coxe, Dr., 71 

Crookes, Sir William, 257, 259 
Crookes’ Tube for Producing 
X-rays (Illustration), 256 
Crus ell, 147 
Cunens, 39 
Cuttriss, 205 
Cyolopses, 4 


Daft, Leo, 213 
D’Alembert, 76 
D’Alibard, 48 
Dal Negro, Abbe, 92 
Damping (of needle), 77 
Dana, I. F., 100 

Daniell, 91, 113, 122, 123, 126, 
128, 160, 161, 219 
Daniell Battery Cell (Illustra¬ 
tion), 115 

Darwin, Charles, 182 
Davenport, Thomas, 107,108, 113 
Davenport’s Motor (Illustration), 
108 

David, King, 3 
Davidson, Robert, 127 
Da Vinci, 20 

Davy, Sir Humphrey, 67, 70, 71, 
76, 78, 83, 86, 178, 251 
Day, 100 
De Changy, 168 
De Forest, 287 
Del any, P. B., 273, 274 
De La Rue, 125 
De La Rive, 172 
Deleuil, 143 

De Moleyns, Frederick, 130, 144 
Desaguliers, 37 
Deville, Prof., 251 
Dewey, Admiral, 281 
Dickerson, William, 189 
Dioscorides. 18 

Diplex Principle (Tel.), diagram 
of, 196 

Direct Current Dynamos (Illus¬ 
tration), 191 

Draper. Dr. John W., 148 
Dry-pile. 72 

Dufay, I)r., 37, 40, 43, 86 
Du Moncel. 213 

Duncan, Prof. Robert Kennedy, 
265, 266 

Duplex-Telegraphy (Stearns-Edi- 
son Method), Diagram of, 193 
Dynamo (first one), 96 
Dynamo, Hjorth’s (Ill.), 152 

Edison, Thomas A., 192, 193, 
195, 200, 207, 213, 215, 216, 
217, 218, 228, 243, 261, 262, 
263, 265, 284 


INDEX 


313 


Edison’s Chemical Meter (Illus¬ 
tration), 208 

Eel, electric, 18 

Electricity, 2; magnet, 14; con¬ 
ductors and nou-conductors, 35; 
i nsulators, 36 ; conduction and 
insulation discovered, 36; vit¬ 
reous and resinous, positive 
and negative, 37; prime con¬ 
ductor and collector, 38 ; Ley¬ 
den jar, 39 ; identity with 
lightning, 44. 45 ; lightning 
rod, 46 ; single fluid theory, 
47 ; induction discovered, 49 ; 
attraction and repulsion, 50; 
static, 52 ; double fluid theory, • 

54 ; coulomb, unit of quantity, 

55 ; electrophorus, 58 ; electro¬ 

scope, 59, 60; Voltaic battery 
or pile, 61; carbons, 69; tor¬ 
pedo, 69; electric-arc, 70; dry- 
pile, 72; identity with mag¬ 
netism, 72; magnetic deflec¬ 
tion, 73; electric motors and 
thermo-electricity, 76; coil, 
helix or solenoid, 78 ; a state, 
not a substance, 84, 85 ; ohm, 
unit of resistance, 89; Ohm’s 
law, 90, 178 ; circuit, 93; 

voltaic-electric-induction and 
magnetic-electric-induction, 93; 
dynamo, 96; “sympathetic 
needles, ” 99; thermopile, 101 ; 
rotary-motor of Jacobi, 104; 
commutators or “changers 
of currents, ” 104, 105, 106 ; 
electric boat, 108 ; voltameter, 
109 ; electrolysis, 109 ; electro¬ 
lyte, 110; ion, 110; electrode, 
110; anode, 111 ; kathode (or 
cathode). 111, 257; voltage, 
111 ; electroplating, typing and 
casting, 112, 125, 126, 130; 
fuse, 128; polarization, 129; 
incandescent lamp, 129, 145 ; 
anomalous magnetism, 131 ; 
induction coils, 132; trans¬ 
formers, 133; “ Joule’s law,” 
137; rheostat, 140; vibration, 

146 ; electric surgical cautery, 

147 ; Page’s motor, 154; theory 


of light as an electric disturber, 
186 ; potential, 190 ; dynamos, 
series-wound, shunt-wound, 

compound-wound, 191, 192 ; 

power (mechanical motion), 
194; electric candle (Jab- 

lochoff’s), 209 ; Blake trans¬ 
mitter, 215 ; ampere, volt, 

ohm, farad, calorie. Joule, 

Watt, 219, 220; rotating mag¬ 
netic held, 227, 228 ; static, 
current and rotating, 234; vi¬ 
bration or radiation, 234; elec¬ 
tric “eye” or detector, 235; 
coherer, 236; tapper, 253; 
fluoroseope, 261 ; oscillator, 
26 i; radiographs and skia¬ 
graphs, 262; conductivity, 
266; baretter, 288; alterna¬ 

tors, 306 
Electrolyte, 110 
Electron, 11 

Electrophorus, The (Illustration), 
58 

Elfinor, 6 
Elias, 171 

Elizabeth, Queen, 23 
Ellsworth, Miss Annie, 141, 142 
Ethiopians, 10, 11 
Etruscans, 3, 4 
Eumaeus, 11 
Euripides, 7 

Faraday, Michael, 22, 69, 70, 
75, 77, 82, 86, 88, 93, 94, 95, 
97, 98, 101, 102, 103, 109, 110, 
111, 112, 120, 122, 131, 132, 
141, 146, 165, 172, 186, 207, 
208, 216, 220, 224, 226.227, 231 
Faraday’s Pise Dynamo, first ever 
built (Illustration), 96 
Faraday’s Experiment in Mag¬ 
netic and Voltaic Induction 
(Illustration), 94 
Farmer, Moses G., 148, 155, 168, 
190, 212 

Ferraris, Prof. Galileo, 228 
Field, Cyrus W., 166, 167, 185 
Field, Stephen D., 218 
Finney, Dr. J. R., 218 
Finsen, Dr,, 294 



314 


INDEX 


Fleming, Prof., 294, 295 
Fluoroscope, The (Illustration), 
261 

Fontaine, 194 

Franklin, Benjamin, 28, 42-52, 
57, 109, 224, 235 
Frictional Electric Machine for 
Producing Static Electricity 
(Illustration), 52 
Frischen, 155 
Fuller, 30 

Galileo, 25 
Gale, Leonard D., 116 
Galvaui, 54, 55, 56, 58, 59, 60, 
61, 62, 63, 86 
Galvaui, Madame, 56 
Galvani’s Experiment with Frog’s 
Legs (Illustration), 55 
Galvanism, 57 
Galvanometer, 80 
Galvanometer for detecting and 
measuring currents (Illustra¬ 
tion), 90 

Galvanometer, mirror form (Il¬ 
lustration), 202 
Gardiner, Samuel, 168 
Gauss, Prof., 120, 122, 147, 178, 
179, 201, 283 
Gautherot, 171 
Gibson, Charles R., 234 
Gilbert, William of Colchester, 
20-29 
Gintl, 155 
Gioia, Flavio, 16 
Goadby, Edwin, 19 
God, 142 

Goldleaf Electroscope (Illustra¬ 
tion), 60 

Gooch, Sir Daniel, 187 
Gordon, 38 

Gramme, 171, 179, 180, 181, 193, 
194 

Gramme’s Machine (Illustration), 
180 

Gravity Cell (Illustration), 161 
Gray, Elisha, 205, 212, 289 
Gray, Stephen, 34, 35, 36, 86 
Gray’s discovery (diagram), 35 
Great Eastern Laying Atlantic 
Cable (Illustration), 188 


Greeks, 3, 4, 9 
Greener, 147 

Grove and Bunsen Cell (Illustra¬ 
tion), 128 

Grove, Sir William Robert, 128, 
172 

Grove’s Incandescent Lamp (Il¬ 
lustration), 129 
Guillemin, 15, 74, 190 

Halske, 155 
Halstead, Murat, 244 
Harrison, Frederic, 34 
Havvksbee, Francis, 30, 33, 38, 
178 

Hebrews, 3 
Helena, 7 
Heliades, 11 

Henry. Prof. Joseph, 87, 88, 91, 
92, 98, 100, 123, 131, 132, 224, 
232, 235, 246 

Henry’s motor (Illustration), 92 
Heracleiau Stone, 14 
Herakles, 14 
Hercules, 14 

Hertz, Prof. Heinrich, 231, 233, 
234, 235, 236, 257, 275 
Hertz’s Detector (Illustration), 
235 

Hewitt, 294 
Hjorth, Soren, 151, 189 
Holtz, 183, 184 
Homer, 4 

Hopkinson, Thomas, 45 
Horace, 7 
House, 164 

Houston. E. J., 40, 56, 83, 84, 
90, 93, 97, 110, 125, 144, 145, 
148, 168, 176, 194, 213, 220, 
227, 276, 296 

Hughes’ Microphone (Illustra¬ 
tion), 214 

Hughes’ Printing Telegraph (Il¬ 
lustration), 163 

Hughes, Prof., 151, 162, 213, 216 
Humboldt, 13, 77 

Iles, George, 224 
Indians, 177 

Insulation and conduction, 27 
Ions, 111 


INDEX 


315 


Isaiah, 10 

Jablochoff, 209, 210, 211 
Jablochofl’s Electric Caudle (Il¬ 
lustration), 210 
Jacksou, Dr., 101 
Jacobi, Moritz, 104, 108, 125, 
140, 194 

Jacobi’s Rotary Motor (Illustra¬ 
tion), 104 
Job, 3 

Joule, James Prescott, 137, 220 
Joule’s Law, 137 
Jupiter, 4, 11, 45 

Kathioks, 111 
Kathode, 111 

Kempenfeld, Admiral, 127 
Kepler, 25 

Key and Sounder, diagram of, 143 
King, 145 

Lacassagne, 162 
Leda’s Twins, 7 
Lenard, 257 

Lenz, 102, 103, 181, 194 
Leonard, Ward, 295 
Lesage, 71 

Leyden Jar and Discharger (Il¬ 
lustration), 39 
Lightning, 2, 3, 4, 5, 7, 8 
Lodestone, 13, 14, 17, 18, 24 
Lodge, Sir Oliver, 232, 233, 234, 
237, 253, 258, 259, 270, 277 
Lucretius, 14, 15 
Lyncurium, 18 

Macmillan & Co., 219 
“Magdeburg Hemispheres,” The 
(Illustration), 31 
“Magic Lyre” of Wheatstone, 
175 

Magnetic Lines of Force, The 
(Illustration), 97 
Magnets, 13, 14 

Magnets, Henry’s and Sturgeon’s 
(Illustration), 87 
Mahomet, 17, 30 
Manilius, 46 
Mann, 216 

Marconi, 253, 269, 275, 276, 280, 
281, 286, 287, 294 


Marconi’s Coherer (Illustration), 
277 

Marconi’s Transmitter and Re¬ 
ceiver, diagram of, 280 
Mariner’s compass, 16, 17, 18 
Maskelyne. Prof., 295 
Masson, 133 

Maver, William, Jr., 288 
Maxwell, J. Clark, 136 
Maxwell, Prof. Clerk, 186, 226, 
231, 232, 283 
Microphone, 213 
Miraud, 154, 155 
Moissan, Prof., 247 
Moore, Prof. D. McF., 264 
Morse, Samuel F. B., 91, 100, 
101, 113, 114, 116, 117, 118, 
119, 120, 123, 130. 135, 139, 
141, 112, 163,164, 203, 236, 299 
Morse’s First Model, Pendulum 
Instrument (Illustration), 117 
Munro, John, 219 
Mushenbroeck, Prof., 39 

Nansen, 247 
Nebuchadnezzar, 12 
Nernst, Prof., 266, 267 
Neumann, 146 

Newton, Sir Isaac, 30, 33, 35, 38, 
182 

Nicholson, 69, 110, 182 
Nobel, Alfred, 294 
Nollet, Abbe, 40, 152 
Norman, Robert, 16, 17, 26, 30 
Northern Lights, 8 

Oersted, Hans Christian, 22, 
72, 73, 79, 81, 93, 99, 100, 124, 
201, 228 

Oersted’s Discovery of Magnetic 
Deflection, diagram of, 73 
Odysseus, 11 

Ohm, George, 89, 90, 156, 178 
Ohm, unit of electrical resistance, 
89, 90 

Ohm’s law, 90 
Orpheus, 7 
Owen, Prof., 99 

PACinotti, Dr., 169, 170, 171, 
179, 194 

Pacinotti’s machine (Illustra¬ 
tion), 170. 


316 


INDEX 


Page, Prof. G. C., 132, 154, 159, 
171, 175, 179 

Page’s Electric Motor (Illustra¬ 
tion), 154 

Peabody, George, 145 
Pedro, Dom, 20 
Peltier, 101 

Peltier Cross (Illustration), 101 
Persians, 4 
Phsetlion, 10, 11 
Phoebus, 11 
Pixii, 105, 106, 107 
Pixii's Dynamo (Illustration), 
105 

Plante, Gaston, 171, 172, 173 
Plante’s Storage Battery (Illus¬ 
tration), 171 
Pliny, 8, 17, 57, 83 
Plinys, The, 57 
Polarity, 105 
Poliak, 281 

Polyphase Induction Motor (Il¬ 
lustration), 230 
Pompey, The Great, 5 
Pope. Franklin L., 143, 223 
Popofif, Prof., 275, 276, 277 
Popoff Wireless Telegraphic Re¬ 
ceiver, diagram of, 276 
Porta, Baptista, 23, 24 
Potamian, Brother, 23, 28 
Pouillet, 123 
Preece, Sir W. H., 280 
Price, Charles Wilson, 303 
Ptolemy, Pliiladelplius, 17 
Pupin, Prof., 286 

Ramsden, 52 

Relay Principle, diagram of the, 

113 

Reis, Johann Philipp, 160, 175, 
176. 177. 214 

Reis Telephone (Illustration), 176 
Rheostat, diagram of the, 140 
Richmann, 48 
Ritchie, 107 
Ritter, 172 

Roentgen, Prof., 256, 259, 260, 
294 

Romagnosi, 71 
Romans, 3, 4 
Romas, 48 


Romulus, 5 
Rotary motors, 93 
Rowland, Prof., 269, 271, 274 
Ruhmkorff, 133, 153, 155, 238 
Ruhmkorff Coil (Illustration), 
134 

St. Augustine, 17 
St. Elmo’s Fire, 7, 18 
Salmoneus, 6 
Salvoni, Prof., 261 
Savary, 123, 131 
Sawyer, 216 

Sawyer-Mann Lamp (Illustra¬ 
tion), 212 

Saxton, Joseph, 107 
Schilling, 122 
Schweigger, 79, 88, 124 
Schweigger’s Multiplier (Illustra¬ 
tion), 80 

Searchlight at work (Illustra¬ 
tion), 268 
Seebeck, 83, 84 

Serrin’s Automatic Regulator (Il¬ 
lustration), 169 
Shakespeare, William, 6 
Siemens’ First Electric Railway 
(Illustration), 217 
Siemens, Dr. Werner, 155, 159, 
179, 190, 194, 196, 217, 218, 
223. 247 

Siemens’ Armature (Illustra¬ 
tion), 160 
Silliman, 100 
Silurius, electric, 18 
Siphon-Recorder and Record, 
diagram, 204 
Smith, 140 
Scunnering, 71, 99 
Spencer, 125, 126 
Spenser, Edmund, 6 
Sprague, Frank J., 241 
Stake, 147 
Stark, Dr. J. B., 195 
Starr, John W., 144, 145. 146,147 
Starr’s Lamp, diagram of. 144 
Stearns. Joseph B., 156. 192 
Steinheil, 116, 120. 121, 122, 141, 
148 

Steinheil’s Improved Receiver 
(Illustration), 121 


INDEX 


317 


Steinraetz, Prof., 293 
Sturgeon, William, 87, 89, 100, 
104, 106 

Swammerdam. Dr., 56 
Symmer, Robert, 43, 51 
Sympathetic needles, 99 

Telautograph, The (Illustra' 
tion), 289 

Telegraph and Telegraphy, 71, 
74; “bubble,’’ 99, ‘ 100; 

‘‘chemical,” 149; condensers, 
158; dots and dashes, 120; 
“diplex,” 195; “duplex,” 
155. 156; “facsimile,” 150; 
pendulum instrument, first 
Morse model, 117 ; polarity, 
196; “ pole-changer, ” 197; 

“printing,” Hughes’, 151, 163, 
164; Wheatstone’s, 130, 131; 

‘‘ quadruplex, ’ ’ Edison’s, 195 ; 
receiver, 118; recorder, 148; 
relay, 113, 148; neutral or 
Stearns’ relay, 156 ; siphon-re¬ 
corder, 204; sounder, 142; 
Steinheil’s discovery, 121 ; 
“submarine,” 135, 136; 

transmitter, 195 
Telegraph one, 302 
Telegraphy by induction from 
moving train, diagram of 
method, 239 

Telephone, 160; “lovers,” 175; 
receiver, 176, 177; switch¬ 

board, 269, 284, 285 
Telephony, wireless, 302 
Tesla, Nikola, 227. 228, 244, 250, 
251, 252, 254, 262, 269, 270, 
271, 282, 301, 305 
Thales, 12, 13, 43, 103 
Theophrastus, 18 
Thiers, 161 

Thompson, Elihu, 71, 74, 169, 
223, 224, 262 

Thompson, Prof. J. .T., 258 
Thompson, Prof. Silvanus P., 
27, 176 

Thomson, William (Lord Kel¬ 
vin), 136, 137, 153, 160, 165, 
201, 202, 203, 204, 260 
Thor, 3 


Thracians, 4 
Tilly, 31 

Torpedo (electric fish), 18, 51, 69 

Tunzelmanu, 202 

Turgot, 46 

Tycho Brahe, 20 

Tyndall, 93, 112 

Vacuum, Torricellian, 178 
Vail, Alfred, 117, 119, 120, 123, 

139, 141, 142, 151, 154 
Vail, Judge, 119 
VanDepoele, Charles J., 223 
Varley, 160, 182, 186, 190 
Victoria, Queen, 167 
Virlag, 281 

Volt, 90 

Volta, Alessandro, 54, 57, 58, 59, 
60, 61, 182, 224 

Voltaic Cells in Multiple Connec¬ 
tion and in Series Connection 
(Illustration) 64 
Voltage, 90 

Volta’s Battery or Pile (Illustra¬ 
tion), 61 
Voltaire, 33 

von Guericke, Otto, 30, 31, 182 
von Helmholtz, Hermann, 136, 
286 

von Kleist, Bishop, 39 

von Welsbach, Dr. Carl, 265, 266 

Wall, Dr., 36 
Ward, H. H., 189 
Watson, Sir William, 40, 43 
Watt, 220 

Weber. Prof., 100, 120, 122, 141, 
147, 178, 179, 201 
Wells, H. G., 226 
Westingliouse, 230 
Wheatstone, Prof., 116, 122, 130, 

140, 141, 145, 148, 149, 162, 
172, 175, 190, 197, 198 

Whewell, Dr., 22 
Wilde. 179 187, 189, 190 
Wimshurst, 184 
Wollaston, Dr., 63, 79, 80, 81 
Wohler, 251 

Young, Brigham, 177 

Zeus, 4 


I 


























